We evaluated the long-term outcome of mitral valve replacement with a Harken caged-disc prosthesis for up to 11 years (range, 50 to 130 months; mean, 81 months) in 170 patients whose mean age was 55 years. The early (30-day) mortality was 11.2% (19 out of 170 patients). Late follow-up information was obtained for 144 (95%) of the 151 survivors. The actuarial survival was 57% at 5 years and 40% at 10 years. Overall mortality was associated with advanced age, male sex, an ischemic origin for the mitral valve disease, and nonuse of warfarin anticoagulation. Late deaths (n=59) were valve-related in 46%, cardiac but non-valve-related in 44%, and noncardiac in 10% of the cases. One thromboembolic event or more occurred in 41 patients (incidence, 5.7% per patient year), 14 of whom died (24% of the late deaths). All four patients who were not on warfarin, aspirin, or other antithrombotic therapy experienced thromboemboli. This complication was correlated with the nonuse of warfarin-type anticoagulation, with mitral regurgitation, and with late cardiac death. Mechanical prosthetic failure resulted in reoperation or death in 7.6% of the late survivors (1.5% per patient year). In 75 patients with normally functioning prostheses, the disc-to-sewing ring ratio was established by means of cinefluoroscopy (0.93 +/- 0.04, mean +/- 25D). Because of the high proportion of cardiac valve-related deaths (46%), the high incidence of late mortality due to thromboembolic events (24%), and the 7.6% incidence of reoperation or death resulting from mechanical valve failure, close follow-up with cinefluoroscopy and continued warfarin anticoagulation (alone or in combination with dipyridamole) are essential after mitral valve replacement with the Harken caged-disc prosthesis.

Impairment of platelet function commonly occurs after cardiopulmonary bypass, and may result in substantial bleeding. Because desmopressin acetate (a synthetic analogue of vasopressin) shortens bleeding time in a variety of platelet disorders, a controlled clinical trial of intravenous desmopressin was performed in 39 patients with excessive mediastinal bleeding (greater than 100 ml/h) and a prolonged template bleeding time (greater than 10 minutes) more than 2 hours after termination of cardiopulmonary bypass. Twenty-three desmopressin recipients and 16 control patients (no desmopressin) were similar in surgical procedure, pump time, platelet count, template bleeding time and amount of bleeding before therapy (p = NS). Compared with the control group, the patients receiving desmopressin (20 micrograms; mean 0.3 micrograms/kg) utilized fewer blood products (29 +/- 19 versus 15 +/- 13 units/patient; p less than 0.05), especially platelets (12 +/- 9 versus 4 +/- 7 units/patient; p = 0.004), while achieving a similarly effective reduction in mediastinal bleeding (4.8- and 4.3-fold, p = 0.001 for both). Severe platelet dysfunction was partially corrected within 1 hour after desmopressin infusion, during which interval no blood products were administered: the template bleeding time shortened (from 17 to 12.5 minutes, p less than 0.05), whereas the platelet count remained unchanged (at 96 +/- 35 and 105 +/- 31 X 10(3)/mm3, p = NS). The plasma levels of two factor VIII components increased: procoagulant activity (VIII:C) from 0.97 +/- 0.43 to 1.52 +/- 0.74 units/ml (p less than 0.05) and von Willebrand factor (VIII:vWF) from 1.28 to 1.78 units/ml (p less than 0.05); these increases correlated with the shortening of the bleeding time (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

The presence of a diffuse slow washout pattern (DSWP) of T1-201 without perfusion defects (PD) during stress-redistribution (ST-RD) imaging has been demonstrated to occur in some pts with extensive myocardial hypoperfusion that is relatively balanced in severity. Because PD analysis alone could misclassify such pts, the authors studied the clinical and prognostic implications of this unique T1 pattern. Of 3080 consecutive pts who had quantitative ST-RD T1 studies, 36 (1.2%) demonstrated DSWP (delayed clearance from anterior, posterior and inferior myocardium) without any PD. Of 19 patients with coronary angiography (angio), 15 (79%) had CAD and 22 (58%) had 3-vessel (TV) or left-main (LM) disease (D). During followup of 17 +- 12 month, 13/36pts (36%) had 15 major cardiac events: death (2), myocardial infarct (4), coronary bypass (9). In 24 pts exercising to <75% of predicted HR, specificity for CAD and extensive CAD remained high (67% and 50%), and 6/14 (43%) had cardiac events. Patients were compared as to the presence (Grp A-25 pts) or absence (Grp B-11 pts) of at least one other indicator of myocardial ischemia (chest pain, ST depression, hypotension, increased lung uptake of T1) during exercise. Angio in 25 Grp A pts revealed CAD in 14 (93%)more » and TVD or LMD in 10 (67%). After 16 +- 13 months, 12 of these 25 (48%) had a cardiac event. Three Grp B pts had angio (2 normal, 1 with TVD) and after 20 +- 9 months, 3 (27%) had cardiac events (2 deaths, 1 infarct). The authors conclude that DSWP with a PD is strongly associated with extensive CAD and major cardiac events, especially when accompanied by other markers of ischemia. Importantly, even when exercise is submaximal and does not result in other signs of mycocardial hypoperfusion, this pattern carries an ominous prognosis.« less

Radionuclide activity within the pericardial (P) space, either localized or surrounding the cardiac chambers, indicates active (P) bleeding when gated equilibrium radionuclide ventriculography (RNV) is performed with Tc-99m-labeled RBCs. To evaluate the ability of RNV to detect and to quantify the amount of accumulated P blood, the authors developed a simulated P bleeding model. By subxyphoid incision, a balloon (BAL) was inserted into the P space of 6 dogs. Images were reviewed to determine the presence and appearance of the P blood pool. Background-subtracted radioactive counts within each detected P blood pool were compared to known volume as a count rate (corrected for heart rate and acquisition duration) and as a fraction of left ventricular end-diastolic (LVED) peak counts. Using 3 views, an abnormal P blood pool was consistently visible at 10 ml when localized (BAL) and at 30 ml when freely distributed (BLD). Radioactive count rates and counts proportional to LVED counts increased (non-linearly) with volume. At 50 ml, the BAL dominated the RNV-BAL images, and a ''ring'' of BLD surrounded the heart in the RNV-BLD images. Thus, multiview RNV consistently detects small volumes of tagged pericardial blood. Measurement of radioactive counts from the pericardial blood pool and itsmore » appearance may allow a quantitative estimate of amount of pericardial bleeding.« less

Moffitt, Emerson MD; Sethna, Dhun MD; Bussell, John MD; Raymond, Marjorie RN; Matloff, Jack MD; Gray, Richard MD Author Information

The desire for a low profile mechanical valve with better fluid dynamic performance led to the design and development of the St. Jude Medical bileaflet prosthesis. Comparative in vitro flow studies indicate that it has better pressure drop characteristics than the Björk-Shiley (convexo-concave) and Carpentier-Edwards porcine valves in current clinical use, especially in the small sizes. In the 21 to 27 mm aortic valve size range the St. Jude valve has an average performance index of 0.66, compared with 0.46 and 0.32 for the Björk-Shiley and Carpentier-Edwards valves, respectively. In contrast, the St. Jude valve has larger regurgitant volumes than both the Björk-Shiley and Carpentier-Edwards valves. Velocity measurements with a laser-Doppler anemometer indicate relatively centralized flow with small amounts of turbulence downstream of the St. Jude valve. The flow is unevenly distributed between the central and side orifices. The turbulent shear stresses are, however, large enough to cause sublethal or lethal damage to blood elements. Wall shear stresses are smaller than those measured downstream of the Björk-Shiley valve. Regions of flow separation were observed just downstream from the sewing ring, which could lead to excess tissue growth along the sewing ring. The results of this study indicate that overall in vitro fluid dynamic performance of the St. Jude valve is superior to that of the two other commonly used prostheses.

In summary, we believe that the impact of our findings on the patient and clinician includes recognition and acknowledgment that transient cognitive dysfunction frequently follows coronary bypass surgery. With this recognition comes the reassurance to the patient and his family that it is a temporary phenomenon that should resolve in time. To help the patient comply with his postoperative instructions during this difficult time period, there should be individual, slow-paced presentation of material with intentional repetition of information to help him remember the specific details of his postoperative instruction; the individual most involved with assisting in the patient's postoperative recovery should be included in all teaching sessions; and instructive audiovisual material should be used in postoperative home care.

To clarify the relationship between angiographic and hemodynamic stenosis severity and the appearance during stress-redistribution myocardial T1-201 scintigraphy (Ex-T1) of a visual (V) or quantitative (Q) perfusion defect (PD) or washout (WO) abnormality, 24 pts with CAD underwent intracoronary pressure gradient study at bypass surgery (CABG). All had pre-CABG Ex-T1 without interval deterioration. The mean diastolic pressure gradient (MDG) measured at reproducible hyperemic flow rates was determined for 34 stenoses (13 LAD, 7 LCX, 14 RCA) and compared with the results of Ex-T1 in subtended myocardial regions (LAD=anterior; LCX=posterolateral; RCA=inferior). Fourteen stenoses (50-99% diameter narrowing) were unassociated with VPD despite maximal exercise: MDG was 9 +- 5mmHg, with MDG/mean aortic diastolic pressure (ADP) ratio of 0.12 +- 0.07. QPD and QWO analysis detected 8 of these. Thirteen stenoses (90-100% severity) led to reversible VPD: MDG was 36 +- 11 mm Hg, MDG/ADP ratio was 0.52 +- 0.17, and Q analysis was abnormal in 12/13. Seven stenoses (90-100% severity) subtended infarcted myocardium: MDG was 42 +- 21 mm Hg, MDG/ADP ratio was 0.52 +- 0.18, and V and Q analyses were abnormal in all. From this study, the authors derive the following conclusion: 1) Ex-T1 correlates better with hemodynamic severity ofmore » stenoses than does angiography; 2) V abnormalities identify stenoses of major angiographic and hemodynamic severity, while Q analysis detects some (57% in this study) stenoses of lesser severity; and 3) stenoses causing reversible Ex-T1 abnormalities present similar hemodynamic impediments to those causing myocardial infarcts.« less

When life-threatening cardiogenic shock (CI 1.8 1/min/m/sup 2/, elevated right and left-side filling pressures) occurs early (0-48 hrs) after open-heart surgery, routine approaches frequently cannot distinguish between expected etiologies: (1) transient systolic failure of the LV, RV, or both, common early postoperatively (postop); (2) perioperative infarct of the LV or RV; (3) myocardial restriction due to active pericardial bleeding or to accumulated clots and fluid; (4) diminished LV reserve from aneurysmectomy; and (5) residual valvular regurgitation. Distinction is critical, because (1), (2), and (4) will be treated by optimizing preload and afterload; (3) with urgent (if active bleeding) or semi-urgent surgery; and (5) with repeat valvular surgery. In 22 pts with unexpected early postop cardiogenic shock, Tc-99m-RBC equilibrium radionuclide ventriculography revealed: global LV (3 pts) or RV (3 pts) dysfunction, new segmental LV dysfunction (2 pts), active bleeding (5 pts) and/or accumulated pericardial fluid ( 8 pts) with hyperdynamic LV and RV, and a small hyperdynamic LV without effusion (1 pt), providing a specific etiologic diagnosis in all cases. In the Cardiac Surgical ICU, therapeutic decisions frequently await and depend on the results of equilibrium radionuclide ventriculography, now routinely performed in postop pts with unexpected cardiogenic shock.