The relationship between mitral inflow velocity patterns and left ventricular end-diastolic pressure (LVEDP) was evaluated using pulsed Doppler echocardiography in 34 cases of heart disease, without significant valvular regurgitation. Flow patterns in 19 of the 34 cases were also examined before and after the elevation of LVEDP by methoxamine infusion, 0.01 mg/kg/min. The ratio of the peak velocities in the atrial contraction phase to that in the rapid filling phase (A/R) and the ratio of mean acceleration rates to peak velocities in the rapid filling phase (ACR/R) were determined from the mitral flow patterns obtained by the apical approach. 1. ACR/R correlated significantly with LVEDP (r = 0.49), but A/R did not. LVEDP in six cases with normal A/R (0.5 to 1.0) was 8.3 +/- 2.9 mmHg (mean +/- SD). Among 19 cases with A/R of 1.0 or more and ACR/R less than 13 sec-1, LVEDP showed 10.2 +/- 3.8 mmHg. In eight cases with A/R of 1.0 or more and ACR/R of 13 sec-1 or more, LVEDP was 17.9 +/- 6.2 mmHg. The average value of LVEDP in two cases with A/R less than 0.5 was 18.5 mmHg. 2. When the LVEDP was elevated after methoxamine infusion, A/R within normal range increased in five of six cases and decreased in the remaining case. A/R more than 1.0 decreased in 10 of 11 cases and ACR/R tended to increase with increasing LVEDP.(ABSTRACT TRUNCATED AT 250 WORDS)
The usefulness of single photon emission computed tomography (SPECT) using technetium-99m pyrophosphate (99mTc-PPi) was evaluated in 15 patients with acute myocardial infarction. SPECT was performed with a rotating gamma camera after conventional planar images were made. Infarct size was measured from transaxial images of myocardial pyrophosphate uptakes. In each slice, the boundary was defined by subtracting 70 percent of the maximal counts and the number of voxels automatically counted. This subtraction rate was determined by phantom study and by comparing SPECT using 99mTc-PPi with thallium-201-gated myocardial scintigraphy (201Tl gated SPECT). The planar images showed diffuse uptakes in two of the 15 patients, and in these cases it was difficult to detect the infarct site. In contrast, SPECT images clearly imaged the infarct site consistent with the electrocardiographic findings, and they were definitely separated from the uptakes in the bones in all cases. Infarct size, ranging from 3.4 ml to 78.3 ml, correlated well with cumulative creatine kinase release (r = 0.84, p less than 0.01, y = 772x + 13900). Correlation of infarct size with peak serum creatine kinase level was also significant (r = 0.66, p less than 0.01, y = 10.6x + 693). In conclusion, SPECT with 99mTc-PPi is a useful means of investigating the spatial distribution of pyrophosphate uptake and of evaluating the size of myocardial infarction.
An aenurysm of a diverticulum of the ductus arteriosus in a 33-year-old man was presented. The chest radiography revealed a mass obscurring the aortic window above the hilus of the left lung. His blood pressure was 130/70 mmHg, and there was no difference in pressures between the upper and lower or between the right and left extremities. A CT scan of the chest showed 30 X 34 mm angioma adjacent to the descending aorta and pulmonary artery. Aortography and contrast radiography of the right ventricle revealed a cystic pedunculated aneurysm at the superior portion of the descending aorta. The base of the left pulmonary artery was slightly displaced. There was no communication between the aorta and pulmonary artery, nor was any significant difference in pressure between the ascending and descending aorta. This case was diagnosed as an aneurysm of the diverticulum of the ductus arteriosus, and then it was resected. The abnormality was confirmed by the localization of the aneurysm and histopathologic findings, but the presence of the ligamentum arteriosum was not confirmed. This is the 23rd case of the aneurysm of the diverticulum of the ductus arteriosus in adults, and the first case in Japan in which the diagnosis was made in a living patient, followed by successful surgery.
Digital subtraction angiography with selective coronary injections of contrast media has enabled us to obtain clear images, not only of the artery, but of the capillary and venous phases of the myocardial perfusion. In the present study, densitometry was used to estimate regional myocardial perfusion dynamics in 10 control cases and 11 anterior myocardial infarction cases. The time density curve showed that contrast material increased rapidly in the arterial phase and appeared to be washed out monoexponentially in the venous phase. The time from the onset of contrast medium injection to the maximal density of the contrast medium (Tp), and the time constant obtained from the washout curve (Tc) were analyzed. In the control group, Tp in the apical region was slightly prolonged as compared with Tp in the anterobasal region, but the difference was not significant (5.2 +/- 0.5 vs 4.2 +/- 0.4 sec: mean +/- SEM). Tc did not definitely change in any portion of the myocardium (anterobasal 5.1 +/- 0.5, anterior 4.8 +/- 0.5, apex 4.6 +/- 0.5 sec, respectively). In anterior myocardial infarction, Tp in the marginal region was significantly prolonged compared to Tp in the control region (6.0 +/- 0.3 vs 4.7 +/- 0.3 sec, p less than 0.01). Tp was prolonged for more than 10 sec in the infarcted region. Tc in the marginal region was markedly prolonged compared to Tc in the control region (7.4 +/- 0.9 vs 4.4 +/- 0.5 sec, p less than 0.025). Tc could not be determined in the infarcted regions because data acquisition time of our apparatus was inadequate.(ABSTRACT TRUNCATED AT 250 WORDS)
201-thallium myocardial imaging studies were performed to evaluate systolic pressures in the right ventricle of 194 patients. These patients were classified to four groups. Group A (95 cases) consists of 77 patients with congenital cardiac disease, five patients with primary pulmonary hypertension, and 13 patients with history of MCLS. Congenital cardiac diseases included 30 patients with tetralogy of Fallot, 20 with ventricular septal defect, nine with atrial septal defect, and eight with pulmonary stenosis. Group B (35 cases); preoperative state of transposition of the great arteries. Group C (43 cases); post-operative state of congenital cardiac disease whose pre-operative right ventricular systolic pressures represented more than 70% of the left ventricular systolic pressures. This group included 31 patients with tetralogy of Fallot, seven with ventricular septal defect, four with atrial septal defect and one with patent ductus arteriosus. Group D (21 cases); post-operative state of transposition of the great arteries. Fifteen min after intravenous infusion of 30-50 microCi/kg 201-TlCl, myocardial images were obtained in five projections (anterior, LAO 30 degrees, 45 degrees, 60 degrees, and lateral). The angles were determined to demonstrate clearly the interventricular septum and the ventricular free wall. The images of end-diastolic phase were obtained using the ECG-synchronized gated method in each projection. The region of interest (ROI) was defined as a section or slice by drawing two lines perpendicular to the septum, and the counts of the systemic and pulmonic ventricular free wall (Cs and Cp) were analyzed to evaluate the pressure of the pulmonic ventricle. The pressures of the ventricles were obtained by cardiac catheterization performed concomitantly with the cardiac imaging.(ABSTRACT TRUNCATED AT 250 WORDS)
The occurrence of a systolic sound in hypertrophic obstructive cardiomyopathy (HOCM) has been well known for more than 20 years. This was phonoechocardiographically regarded as the sound coincident with the abrupt halt of the systolic anterior movement (SAM) of the mitral valve echo, and it has been termed the SAM sound. A 58-year-old man with HOCM was admitted with right hemiplegia. He was found to have a SAM sound which waxed and waned in intensity, and at times moved earlier into systole. He was studied by cardiac catheterization, M-mode and two-dimensional Doppler echocardiography (pulsed, continuous wave and color flow Doppler methods). Asymmetric septal hypertrophy (interventricular septal thickness = 25 mm, left ventricular posterior wall thickness = 14 mm), as well as SAM and midsystolic aortic valve closure were demonstrated. The presence and intensity of the sound was not related to rhythm (normal sinus rhythm vs atrial flutter), heart rate, respiration, position, or inhalation of amyl nitrite. Two-dimensional Doppler echocardiography revealed the following: 1. In the left ventricular outflow tract just below the aortic valve, a systolic turbulent flow was always present. 2. In the left ventricular chamber near the apex, a systolic laminar flow was interrupted in those cycles where the SAM sound was present. Otherwise, in cycles lacking the SAM sound, laminar flow in this locality continued throughout systole (even shorter duration than normal). 3. In the left ventricular inflow tract, diastolic flow was unaffected by the presence of the sound. 4. No mitral regurgitation was observed using color flow Doppler echocardiography. In summary, a SAM sound appeared to be associated with sudden deceleration of blood flow from the apex to the mid left ventricle.
To clarify the correlation between the configuration of the left ventriculogram and serial ECG changes, 16 patients with hypertrophic cardiomyopathy (HCM) associated with asymmetrical septal hypertrophy were examined. In the right oblique view at end-diastole, the configurations were classified by form as round (R, n = 7), round with inferior concavity (R-i, n = 2), spade (S, n = 4) and spade with inferior concavity (S-i, n = 3). These patients were divided into two groups according to serial T wave changes; nine with marked changes (A group) and seven without (B group). Furthermore, group A was separated into two subgroups; seven with increasing negativity or appearance of the negative T wave (A-1 group) and two with decreasing negativity or disappearance of the negative T wave (A-2 group). The results were as follows: Five (71%) of the seven cases with the S and S-i form belonged to the A group. Their apical walls showed marked hypertrophy and their ECGs showed deep negative T waves. The other two cases (29%) belonged to the B group, and did not show marked apical hypertrophy. Four (44%) of the nine cases with the R and R-i form belonged to the A group. They showed mild apical hypertrophy, and initially did not show deep negative T waves. A deep negative T wave appeared in three during observation. The initial depth of the maximum negativity of T wave correlated significantly with apical wall thickness, SV1 + RV5, and the total depth of the negative T wave in precordial leads. During the observation, the A-1 group showed a marked increase of SV1 + RV5. The A-2 group showed a decrease of SV1 + RV5. In conclusion, HCM with deep negative T waves has a tendency to present wide changes in the T wave during serial ECG observation and to show apical hypertrophy on left ventriculography. Cases of increasing negativity of the T wave showed marked increase in voltage of SV1 + RV5. However, cases of decreasing negativity of the T wave showed decreasing SV1 + RV5. These ECG changes, especially the negative T wave changes are reputed to be related to apical wall thickness.
Collapse of the right ventricle and right and left atria is observed in cardiac tamponade. To assess the diagnostic value of each collapse component in identifying cardiac tamponade, two-dimensional and M-mode echocardiograms were recorded simultaneously with the measurement of intrapericardial pressure in five patients as they underwent pericardiocentesis. Before pericardiocentesis, each patient had evidence of right ventricular and right atrial collapse. In addition, left atrial collapse was observed in four patients. During pericardiocentesis, left atrial collapse initially resolved accompanied by a drop in pressure in the pericardial sac. Continuous drainage of pericardial effusion resulted in significant symptomatic improvement and the cessation of paradoxical pulse at the point of resolution of right ventricular collapse. However, right atrial collapse persisted after resolution of right ventricular collapse, but it was absent when pericardiocentesis was completed. Injection of saline solution with heparin into the pericardial sac for cleansing initially caused right atrial collapse, while right ventricular collapse developed with the appearance of cardiac tamponade. In one patient, the simultaneous recording of right ventricular and intrapericardial pressures and two-dimensional echocardiograms demonstrated that right ventricular collapse occurred early in diastole, when intrapericardial pressure exceeded right ventricular pressure. In conclusion, right ventricular collapse is the most reliable sign of cardiac tamponade. Right atrial collapse occurs in the early stage of cardiac tamponade. Left atrial collapse appears very late in the course of hemodynamic deterioration due to cardiac tamponade.
High pulse repetition frequency (HPRF) Doppler and continuous wave (CW) Doppler methods were used to estimate the pressure gradient across the mitral valve. Twenty-two cases of mitral stenosis and five cases of ischemic heart disease were studied. Both the HPRF and CW Doppler studies were conducted during catheterization in all cases. In the Doppler study, pressure gradient was calculated using the simplified Bernoulli's formula. The HPRF device used was a type SSD-730 produced by Aloka Co. It had a reference frequency of 2 MHz. Its minimum pulse repetition frequency was 4.2 KHz; its maximum, 19.2 KHz. Among the 27 cases, the maximum flow velocity measured by the HPRF method at the level of the mitral valve orifice was compared with that by the CW method. As the velocity increased, the discrepancy of measured values between the two methods increased, but it was within 0.1 m/sec. Therefore, there was a good correlation between the HPRF and CW methods (r = 0.98). The pressure gradient between time delay-corrected pulmonary artery wedge pressure and left ventricular pressure was compared with that obtained by the HPRF method. Contrary to our expectations, the correlation coefficient between the two was not so high, and the pressure gradients calculated by the HPRF method tended to be underestimated. For eight patients in whom the left atrial pressure could be recorded, the pressure gradient between the left atrium and left ventricle was compared with that obtained by the HPRF method. There was underestimation, and a good correlation coefficient was obtained. When using pulmonary artery wedge pressure as a substitute for left atrial pressure, one must realize that the time delay varies in every case and that the pressure pulse itself is not the same. When the pressure gradient between the left atrium and left ventricle is used, a good correlation coefficient can be obtained. Therefore, the flow velocity obtained by the HPRF method will reflect the true pressure gradient across the mitral valve. The HPRF method proved to have a potential equal to that of the CW method for estimating mitral valve flow velocity in mitral stenosis, and it may be used as a helpful diagnostic tool.
Left ventricular end-diastolic pressure (LVEDP) was estimated noninvasively using cardiac parameters obtained from simultaneous recordings of the echocardiograms, electrocardiograms and phonocardiograms in 30 patients who underwent diagnostic left cardiac catheterization. Special attention was paid to the mitral valve motion which reflects global left ventricular function. The interval from the onset of the Q wave of the ECG to the echocardiographic C point of mitral valve closure (Q-C), the interval from the aortic component of the second heart sound to the E point of the mitral echogram (IIa-E), and the time from the opening of the mitral valve (D point) to the E point (D-E) were measured. A good correlation with LVEDP was observed with Q-C/IIa-E (r = 0.87, p less than 0.001), and inversely with D-E time (r = -0.81, p less than 0.001). The correlation of Q-C/D-E and LVEDP was most significant (r = 0.89, p less than 0.001). The regression equations were LVEDP = 36.6 X (Q-C/IIa-E) -10.9 and LVEDP = 4.49 X (Q-C/D-E) +5.56. This noninvasive and easily repeated method for predicting LVEDP is very useful clinically.
To assess the prosthetic aortic valve functions according to types and sizes of valves, the peak flow velocity was recorded by means of continuous wave Doppler echocardiography in 40 patients (age 45 +/- 15 years) with prosthetic aortic valves and in 25 normal subjects. Twenty-one patients had Björk-Shiley valves (1-18 months after replacement); 12 had St. Jude Medical valves (6-48 months after replacement); and seven had Carpentier-Edwards porcine xenografts (48-84 months after replacement). The peak blood flow velocity across the prosthetic valve was recorded at the left ventricular apex, the suprasternal notch, and the right parasternal border in the second intercostal space. The pressure gradient was derived from the peak flow velocity by means of the simplified Bernoulli equation (P = 4V2). The peak and mean flow velocities and the peak and mean pressure gradients were measured to evaluate the opening function of the prosthetic valves. The results were as follows; The peak flow velocities were recorded in 33 patients (83%) with aortic valve replacements. All four measurements were significantly greater in patients with prosthetic aortic valves than in normal subjects, but there was no significant difference according to the valve type. The opening function was less in patients with smaller valves than in those with larger ones. There was a clear correlation between opening function and valve size. We concluded that continuous wave Doppler echocardiography is a useful noninvasive method for evaluating the opening function of a prosthetic aortic valve.
A new computer system was proposed to evaluate abnormal motion of the ventricular wall in patients with myocardial infarction. Multi-slice ECG-gated cardiac X-ray CT (MSECT), a new technique developed in our laboratory, was the source of the original image. Using this system, we reconstructed three-dimensional images, calculated % shortening values of the entire heart, and visualized abnormal wall motion on the ventricular surface, displaying three-dimensionally. Our initial study of five patients with myocardial infarction showed good correlation between the findings using this system and conventional echocardiography and cine-ventriculography. Since the development of the ECG-gated method, the application of CT to the study of heart diseases has progressed rapidly. In patients with myocardial infarction, ECG-gated cardiac CT is used to visualize infarcted myocardium and to evaluate impaired cardiac function. However, such analyses were limited to single slices, because a large dose of contrast medium was required to distinguish the ventricular chamber from the myocardium. By adopting multi-slice ECG-gated cardiac X-ray CT images as the data source and using three-dimensional reconstruction technique, this system is useful for evaluating abnormal wall motion.
ECG-gated magnetic resonance imaging (MRI) was performed for healthy volunteers and for patients with various heart diseases, and its usefulness was compared with that of two-dimensional echocardiography. For this study, several modifications were made in the MRI equipment used. First, a surface coil was introduced for recording the MR signal, resulting in a high S/N ratio. Second, an oblique scan mode was developed for selecting freely the slices similar to those chosen by two-dimensional echocardiography. For imaging, the back projection method and spin echo (SE) pulse sequence were chosen to minimize motion artifacts caused by cardiac beats. In this study, left ventricular wall thickness and left ventricular volume were estimated from gated MR images, taken both in the horizontal and oblique longitudinal scan modes. The results were as follows: The anterior, inferior and apical left ventricular walls were clearly visualized with oblique longitudinal scan images. The thickness of the interventricular septum and posterior wall were measured on left ventricular horizontal scan images. Each measurement was compared with data obtained by two-dimensional echocardiography. Both correlation factors were about 0.70, indicating poor correlations. Left ventricular ejection fraction was calculated from left ventricular volume estimates. Comparison of left ventricular ejection fractions estimated by MRI and two-dimensional echocardiography revealed a close similarity. We concluded that MRI is useful for non-invasive evaluation of cardiac function, and in detecting wall thickness abnormalities due to various heart diseases.
To elucidate the physioanatomic roles of the pericardium, the alterations in gross anatomy and cardiac motion induced by posture were examined by two-dimensional echocardiography in seven patients with total absence of the left pericardium. Ten healthy subjects were served as controls. The heart was located deeper within the chest at end-diastole in patients with pericardial defect than in healthy subjects, especially in the left lateral decubitus position. With progression of systole, the cardiac apex swung anteriorly with the cardiac base as the fulcrum, and the heart approximated the normal position at end-systole. The deeper the position of the center of the cross-section of the left ventricular cavity at end-diastole, the more exaggerated the swinging motion in systole. The deep location of the heart in end-diastole is considered to result from release from pericardial support, and the systolic tonus of the cardiac muscle restores the apex to nearly normal position. The characteristic swinging motion of the heart and its alterations dependent of posture seemed the signs suggestive of total absence of the pericardium. The shape of the short-axis view of the left ventricular cavity was nearly circular throughout the cardiac cycle. Therefore, paradoxical motion of the ventricular septum observed on M-mode echocardiography in pericardial defect results from the anterior shift of the entire heart overcoming the proper motion of the interventricular septum. The left ventricular dimension become enlarged according to the postural change from the right to left lateral decubitus positions regardless of the presence or absence of the pericardium. The right ventricular cavity became enlarged in the left lateral decubitus position in patients with pericardial defect. The elevation of hydrostatic pressure due to postural change was considered excessive due to the absence of the pericardium. In the left lateral decubitus position, systolic excursions of the mitral and tricuspid rings became more prominent in healthy subjects, whereas these excursions, particularly of the tricuspid ring, were reduced in patients with pericardial defect. Depressed tricuspid ring motion was also observed in the right lateral position in cases with pericardial defects. The reduced excursion of the tricuspid, ring and the right ventricular dilatation may affect systemic venous return to the right atrium.
A 67-year-old man with a sigmoid septum causing the left ventricular outflow obstruction by inotropic stimulation was reported. This patient was admitted to the Hospital of the University of Tsukuba because of chest pain. Phonocardiography revealed a systolic ejection murmur which was intensified by amyl nitrite inhalation. A carotid pulse tracing showed a mid-systolic dip and a secondary slow wave during amyl nitrite inhalation. M-mode echocardiography demonstrated neither systolic anterior motion of the mitral valve (SAM) nor mid-systolic closure of the aortic valve at rest. Two-dimensional echocardiography revealed a basal interventricular septum markedly protruding into the left ventricle (sigmoid septum). The remainder of the septum and the left ventricular free wall were not hypertrophied, and no enlargement of the left ventricular cavity was observed. During exercise tests, blood pressure dropped significantly. Cardiac catheterization showed a pressure gradient within the left ventricle with isoproterenol infusion and post-extrasystolic potentiation. These findings suggest that left ventricular outflow tract obstruction could occur in a patient with sigmoid septum by inotropic stimulation, producing a fall of blood pressure during exercise.
A two and a half year follow-up study of segmental left ventricular wall motion was performed by two-dimensional echocardiography for 26 patients with dilated cardiomyopathy (DCM). Segmental analysis of left ventricular wall motion abnormalities (WMA) was performed using 11 segments obtained by short- and long-axis views of the left ventricle. Wall motion in each segment was classified and assigned a numerical score as normal (0), hypokinetic (1), severely hypokinetic (2), and akinetic or dyskinetic (3). Based on this categorization, a wall motion abnormality index (WMAI) was derived as an overall assessment of left ventricular asynergy. The intersegmental standard deviation of the wall motion abnormality score was used as an index of left ventricular asynergy (non-uniformity index: NUI). During the follow-up period, the wall motion abnormality index increased in all of the 26 patients (from 1.23 to 1.82, p less than 0.001), but the non-uniformity index did not change (from 0.72 to 0.73). When comparing the non-uniformity index among three groups classified according to the grade of wall motion abnormality, both at the initial and during follow-up studies, the moderate wall motion abnormality group (1.0 less than or equal to WMAI less than 2.0) had larger non-uniformity indexes (0.83, 0.84) than the other groups, and the severe non-uniformity index (greater than or equal to 0.9) was observed solely in the moderate group. In the follow-up study, these 26 patients were categorized in two groups.(ABSTRACT TRUNCATED AT 250 WORDS)
This is a report of a patient with mitral valve prolapse (MVP) and myocardial abnormalities on endomyocardial biopsy in whose relatives hypertrophic cardiomyopathy (HCM) was identified. A 19-year-old woman was admitted to our hospital for evaluation of a heart murmur. A systolic ejection murmur was audible in the third intercostal space at the left sternal border, and a standard 12-lead electrocardiogram showed ST-T wave changes in leads II, III and aVF. Echocardiography revealed prolapse of the anterior leaflet of the mitral valve, but no left ventricular hypertrophy. Endomyocardial biopsy disclosed mild hypertrophy and disarrangement of the myocardium. The family study revealed asymmetrical septal hypertrophy in her mother, who had no history of hypertension. Her younger sister had mild hypertrophy of the interventricular septum on echocardiography, and her histopathological findings suggested a diagnosis of HCM. This case was clinically regarded as MVP, but development of left ventricular hypertrophy as noted in her mother may occur in the future.
The clinical validity and some problems concerning pulsed Doppler echocardiography (PD) in non-invasive estimates of pressure difference (delta P) across a ventricular septal defect were studied. The maximum velocity (max V) of the left to right shunt flow in the right ventricle was converted to delta P using the simplified Bernoulli equation: delta P = 4V2. We also used the equation: delta P = 4(V2(2) - V1(2)) to estimate the delta P in cases who had left to right shunt flows of high velocity in the left ventricle. Simulatenous recordings of both left and right ventricular pressures and PD were obtained during cardiac catheterization of 11 cases. Accurate Doppler estimates of delta P only from the maximum velocity of the left to right shunt flow in the right ventricle were impossible in nine cases whose actual delta P's were large (more than 41 mmHg) and also in eight cases whose right ventricular systolic pressure was high (either equal to or higher than left ventricular systolic pressure). Besides these 17 cases, delta P estimated by PD using the simplified Bernoulli equation in 39 cases, with pansystolic left to right shunt flows in the right ventricle, correlated well with the actually measured delta P (Y = 0.99X + 2.77, r = 0.91, p less than 0.01). The difference in the maximal instantaneous pressure gradient and Doppler delta P was considered insignificant (between 0 and 7 mmHg, mean 4 mmHg). In nine cases, the left to right shunt flows of relatively high speed (0.63 approximately 2.00 m/sec, mean 1.31 m/sec) were observed also in the left ventricle, and calculated delta P using the simplified Bernoulli equation overestimated the actually measured delta P by 2 to 16 mmHg (Y = 1.52X + 4.88, r = 0.95, p less than 0.01). However, if the delta P is estimated by using the equation, delta P = 4(V2(2) - V1(2)), without ignoring the maximum speed in the left ventricle (V1), it correlates well with the actually measured delta P (Y = 1.07X + 0.76, r = 0.98, p less than 0.01). Thus, in cases with left to right shunt flows with high speeds in the left ventricle, the equation: delta P = 4(V2(2) - V1(2)) was more accurate in estimating the delta P by pulsed Doppler echocardiography.
This is a report of two brothers, six and five years of age, with systemic carnitine deficiency and cardiomyopathy, whose symptoms were improved after oral administrations of DL-carnitine. They had had progressive muscle weakness since three years of age. The elder brother's radiograph on admission showed cardiomegaly with a cardiothoracic ratio of 60%, and his electrocardiogram showed left ventricular hypertrophy and tall, peaked T waves in the precordial leads. The echocardiogram showed slight thickening of the cardiac muscle and decreased ejection fraction. Skeletal muscle biopsy specimens and sera were assessed for carnitine content. The skeletal muscle specimens revealed lipid storage myopathy, and the carnitine contents of the skeletal muscle and sera were both decreased. Myocardial biopsy for the elder brother revealed mitochondrial accumulation. Cardiomyopathy caused by carnitine deficiency is often fatal, but may be cured. Carnitine deficiency should be considered whenever a patient with cardiomegaly and progressive skeletal muscle weakness is encountered.
To evaluate the usefulness in diagnosing coronary artery disease (CAD), dipyridamole-loading 201T1 myocardial scintigraphy was performed for 52 elderly patients (65-92 years, mean: 72 years), and the results were compared with data from the treadmill exercise tests. Thirty-five patients could not tolerate adequate exercise tests. Seven of them had reversible defects; six, fixed (irreversible) ones. Dipyridamole scintigraphy is therefore applicable in detecting CAD among patients with suspected CAD who are unable to perform adequate exercise tests. Four of 16 patients with positive exercise tests had no reversible defects; the exercise results in three were regarded as false positives. Seventeen patients experienced chest pain; 12 had ST depression during dipyridamole loading. There were no serious complications, but seven patients required aminophylline. We demonstrated previously that the sensitivity and specificity of dipyridamole scintigraphy in detecting CAD were 90% and 92%, respectively, in patients with chest pain undergoing coronary angiography. These results were superior to those of conventional exercise myocardial scintigraphy. Therefore, dipyridamole scintigraphy is regarded as a safe and useful method for detecting CAD, particularly in elderly patients who have ST and T wave abnormalities but cannot tolerate exercise test adequately.
