This article reviews available evidence regarding hypertension management in the Asia-Pacific region, focussing on five research questions that deal with specific aspects: blood pressure (BP) control, guideline recommendations, role of renin–angiotensin–aldosterone system (RAAS) inhibitors in clinical practice, pharmacological management and real-world adherence to guideline recommendations. A PubMed search identified 2537 articles, of which 94 were considered relevant. Compared with Europeans, Asians have higher systolic/diastolic/mean arterial BP, with a stronger association between BP and stroke. Calcium channel blockers are the most-commonly prescribed monotherapy in Asia, with significant variability between countries in the rates of angiotensin-converting enzyme inhibitors (ACEis)/angiotensin-receptor blockers (ARBs) and single-pill combination (SPC) use. In clinical practice, ARBs are used more commonly than ACEis, despite the absence of recommendation from guidelines and clinical evidence supporting the use of one class of drug over the other. Ideally, antihypertensive treatment should be tailored to the individual patient, but currently there are limited data on the characteristics of hypertension in Asia-Pacific individuals. Large outcome studies assessing RAAS inhibitor efficacy and safety in multi-national Asian populations are lacking. Among treated patients, BP control rates were ~ 35 to 40%; BP control in Asia-Pacific is suboptimal, and disproportionately so compared with Western nations. Strategies to improve the management of hypertension include wider access/availability of affordable treatments, particularly SPCs (which improve adherence), effective public health screening programs targeting patients to drive health-seeking behaviours, an increase in physician/patient awareness and early implementation of lifestyle changes. A unified Asia-Pacific guideline on hypertension management with pragmatic recommendations, particularly in resource-limited settings, is essential.

Background Dobutamine effects on the relationships of the peak velocity of left ventricular (LV) long-axis systolic motion (s ') with systolic excursion (SExc), systolic duration (SDur) and heart rate, of LV long-axis early diastolic excursion (EDExc) with SExc, and of the peak velocity of LV long-axis early diastolic motion (e ') with EDExc, early diastolic duration (EDDur) and isovolumic relaxation time (IVRT') are unknown. Methods Two groups of adult subjects, one young and healthy (n = 10), and one with impaired LV long-axis function (n = 10), were studied, with the aim of identifying consistent findings for the two groups and for the septal and lateral walls. Dobutamine was infused at doses of 5 and 10 mu g/kg/min. The relationships between tissue Doppler imaging (TDI) variables acquired before and during dobutamine infusion were analysed using mixed effect multivariate regression modelling. Results In both groups, heart rate increased and SDur decreased during dobutamine infusion, and there were independent inverse correlations of SDur with heart rate and dobutamine dose. In contrast, there was no change in EDDur during dobutamine infusion, and no consistent changes in IVRT' independent of heart rate. s ' was positively correlated with SExc and inversely correlated with SDur, and there were positive correlations between EDExc and SExc and between e ' and EDExc. Conclusion Dobutamine increases s ' due to effects on both systolic excursion and duration and it increases e ' due to the associated increases in systolic and early diastolic excursion. A lack of effect on diastolic times does not support the presence of a lusitropic effect of dobutamine.

We would like to thank Professor Čulić and colleagues for their interest in our paper [[1]Sutherland N. Dayawansa N.H. Filipopoulos B. Vasanthakamur S. Narayan O. Ponnuthurai F.A. et al.Acute coronary syndrome in the COVID-19 pandemic: reduced cases and increased ischaemic time.Heart Lung Circ. 2021; https://doi.org/10.1016/j.hlc.2021.07.023Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar] and for their comments [[2]Čulić V. AlTurki A. Proietti R. Letter to the Editor regarding: acute coronary syndromes in the COVID-19 pandemic: reduced cases and increased ischaemic time by Sutherland et al.Heart Lung Circ. 2022; 31 (Heart Lung Circ. 2022;31(3):e32-3): 69-76Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar]. We agree that multiple factors contributed to both a reduction in acute coronary syndrome (ACS) presentations during the first and second waves of the COVID-19 pandemic in Melbourne, as well as for the rebound in presentations when restrictions were eased. In their letter. Professor Čulić et al. identify reduced air pollution and physical activity as causes for reduced ACS presentations. Public health restrictions resulted in reduced air and noise pollution levels in Melbourne during the first and second waves of the pandemic in 2020 [[3]Boroujeni M. Saberian M. Li J. Environmental impacts of COVID-19 on Victoria, Australia, witnessed two waves of Coronavirus.Environ Sci Pollut Res Int. 2021; 28: 14182-14191Crossref PubMed Scopus (31) Google Scholar]. However, when pandemic restrictions eased pollution levels returned to average which does not plausibly explain the rebound 20% increase in ACS presentations that occurred in our cohort. Similarly, restrictions reduced opportunity to participate in team sport and exercise, but possibly increased time to participate in regular physical activity. This is reflected by an Australian survey of 272 adults which reported 44% of adults reduced exertion during the pandemic, but 23% increased their physical activity [[4]GembaPhysical activity during COVID-19 lock-down. Insights into Australians’ physical activity and fitness during the covid-19 shut-down.http://thegembagroup.com/wp-content/uploads/2020/04/GEMBA_COVID-19_Insights_Sports-and-Physical-Activity-Participation__290420.pdfDate: 2020Google Scholar]. The contribution of psychological stressors to ACS presentations in our cohort is difficult to ascertain. Psychological stressors were highly prevalent throughout the pandemic with a high prevalence of depression, anxiety and insomnia noted in multiple studies. Psychological distress was enhanced by isolation and unemployment [[5]Prata Ribeiro H. Ponte A. Raimundo M. Reis Marques T. Mental health risk factors during the first wave of the COVID-19 pandemic.BJPsych Open. 2021; 7: e195Crossref PubMed Scopus (1) Google Scholar,[6]Shi L. Lu Z.A. Que J.Y. Huang X.L. Liu L. Ran M.S. et al.Prevalence of and risk factors associated with mental health symptoms among the general population in China during the Coronavirus disease 2019 pandemic.JAMA Netw Open. 2020; 3: e2014053Crossref PubMed Scopus (4) Google Scholar]. However, our study noted a reduction in presentations when psychological stressors were high. As restrictions eased, social isolation was reduced and people returned to work, yet we found a rebound increase in ACS presentations. There are multiple possible triggers for the rebound in ACS presentations. The degree to which they contribute to the increased presentations requires further research. Increased population vulnerability during the pandemic has been well established with higher rates of snacking, smoking and alcohol consumption reported in the Australian population [[7]Bakaloudi D.R. Jeyakumar D.T. Jayawardena R. Chourdakis M. The impact of COVID-19 lockdown on snacking habits, fast-food and alcohol consumption: a systematic review of the evidence.Clin Nutr. 2021; Abstract Full Text Full Text PDF Scopus (32) Google Scholar,[8]Gravely S. Craig L.V. Cummings K.M. Ouimet J. Loewen R. Martin N. et al.Smokers' cognitive and behavioural reactions during the early phase of the COVID-19 pandemic: findings from the 2020 ITC four Country Smoking and Vaping Survey.PLoS One. 2021; 16: e0252427Crossref PubMed Scopus (8) Google Scholar]. However, it is unlikely that less than one year of unhealthy lifestyles would result in a 20% increase in presentations that coincided with the easing of restrictions. In our anecdotal experience, some patients delayed presentation due to fear of contracting COVID-19 as well as a desire to avoid burdening the health care system. Identification of mechanisms that increase population cardiovascular vulnerability and trigger ACS, which can be addressed by population health measures should be a focus of further research. Campaigns have been developed to address the reduced cardiac presentations such as the American Heart Association’s ‘Don’t Die of Doubt’ campaign and the European Society of Cardiology ‘You can’t pause a heart’ effectiveness should be evaluated and adapted to improve access to cardiovascular health care [[9]American Heart AssociationDon’t Die of Doubt 2020.https://www.heart.org/en/health-topics/dont-die-of-doubtGoogle Scholar,[10]European Society of CardiologyYou can’t pause a heart 2021.https://www.cantpauseaheart.org/Google Scholar]. Respectfully Letter to the Editor Regarding: Acute Coronary Syndrome in the COVID-19 Pandemic: Reduced Cases and Increased Ischaemic Time by Sutherland et al. Heart Lung Circ. 2022;31(1):69-76Heart, Lung and CirculationVol. 31Issue 3PreviewSutherland and colleagues recently reported a reduction in patients admitted with acute coronary syndrome (ACS) and an increase in total ischaemic time during the first and second wave of the COVID-19 outbreak in Melbourne [1]. They also observed a 20% rebound increase in ACS presentations following the relaxation of public health restrictions in November–December 2020 compared to the same period of 2019 and suggested that this could represent long-term sequelae of untreated ACS including reinfarction and heart failure. Full-Text PDF

CLINICAL INTRODUCTION A female teenager presented with palpitations. The baseline rhythm on her ECG demonstrates sinus rhythm with normal PR interval of 120 ms, a mild degree of delta wave, RSR′ morphology in V1 with a precordial transition zone between V1 and V2. The frontal axis demonstrates normal QRS axis, in particular a positive lead III and aVF vectors, and negative aVR and aVL vectors, suggesting an overall inferior propagating QRS vector. Intermittently, however, she exhibits a different QRS morphology and a different ventricular activation vector (lead III and aVL), annotated with black arrows in figure 1.

Several studies have demonstrated a bidirectional relationship between obstructive sleep apnea and primary aldosteronism (PA); however, many of these studies are limited to patients with known obstructive sleep apnea, hypertension, or PA. We evaluated the role of screening for PA in all patients referred for a diagnostic sleep study without selecting for prior diagnoses with these conditions. Plasma aldosterone and renin concentration were measured after an overnight polysomnography. Blood pressure was measured at the sleep center for all patients, while a proportion underwent 24-hour blood pressure monitoring. Of the 85 participating patients, 2 (2.4%) were identified to have likely PA based on an elevated aldosterone:renin ratio and/or clinical characteristics. Another 10 (11.8%) were identified to have possible PA based on their low or normal plasma renin concentration despite taking antihypertensive medications that are known to elevate renin. In participants with both obstructive sleep apnea and hypertension (n=40), the prevalence of likely or possible PA was 30%. However, there was no correlation between aldosterone, rennin, or aldosterone:renin ratio and the apnea-hypopnea index using multiple regression analysis adjusted for interfering medications and hypertension status. The observed high prevalence of possible PA among those with both hypertension and obstructive sleep apnea suggests that they should be routinely screened for PA.

BACKGROUND:The COVID-19 pandemic has led to unprecedented stress on health care systems, and has affected acute coronary syndrome treatment at every step. This study aimed to examine the impact of COVID-19 on patient presentations with acute coronary syndromes during the first and second pandemic wave in Melbourne, Victoria.METHOD:A retrospective cohort study of adults presenting with cute coronary syndrome during the first pandemic wave from 1 March 2020 to 31 April 2020 and the second pandemic wave from 1 July 2020 to 31 August 2020 was compared to a control period from 1 March to 31 April 2019 at a single sub-tertiary referral centre in Melbourne, Victoria servicing a catchment area with a relatively high incidence of COVID-19 cases.RESULTS:Three-hundred-and-thirty-five (335) patients were hospitalised with acute coronary syndromes across all three time periods. The total number of patients presenting with an acute coronary syndrome was reduced during the pandemic, with a higher proportion of ST elevation myocardial infarctions. Ischaemic times increased with time from symptom onset to first medical contact rising from 191 minutes in the control period to 292 minutes in the first wave (p=0.06) and 271 minutes in the second wave (p=0.06). Coronary angiography with subsequent revascularisation significantly increased from 55% in the control period undergoing revascularisation to 69% in the first wave (p<0.001) and 74% in the second wave (p<0.001).CONCLUSION:A concerning reduction in acute coronary presentations occurred during the COVID-19 pandemic, associated with longer ischaemic times and a higher proportion requiring revascularisation. It is crucial that public awareness campaigns are instituted to address the contributing patient factors in future waves.

Primary aldosteronism (PA) is a potentially curable cause of hypertension associated with worse cardiovascular prognosis than blood pressure‐matched essential hypertension (EH). Effective targeted treatment for PA is available with the greatest benefit seen if treatment is started early, prior to the development of end‐organ damage. However, PA is currently substantially under‐diagnosed. The standard screening test for PA, the aldosterone‐to‐renin ratio (ARR), is performed infrequently in both primary and tertiary care. In contrast, ambulatory blood pressure monitoring (ABPM) is frequently utilized in the assessment of hypertension. The aim of this study was to compare ABPM parameters in hypertensive patients with and without PA, in order to identify features of ABPM associated with PA that can prompt screening.

BACKGROUND:Hyperphosphatemia is associated with increased fibroblast growth factor 23 (FGF23), arterial calcification, and cardiovascular mortality. Effects of phosphate-lowering medication on vascular calcification and arterial stiffness in CKD remain uncertain.METHODS:To assess the effects of non-calcium-based phosphate binders on intermediate cardiovascular markers, we conducted a multicenter, double-blind trial, randomizing 278 participants with stage 3b or 4 CKD and serum phosphate >1.00 mmol/L (3.10 mg/dl) to 500 mg lanthanum carbonate or matched placebo thrice daily for 96 weeks. We analyzed the primary outcome, carotid-femoral pulse wave velocity, using a linear mixed effects model for repeated measures. Secondary outcomes included abdominal aortic calcification and serum and urine markers of mineral metabolism.RESULTS:A total of 138 participants received lanthanum and 140 received placebo (mean age 63.1 years; 69% male, 64% White). Mean eGFR was 26.6 ml/min per 1.73 m2; 45% of participants had diabetes and 32% had cardiovascular disease. Mean serum phosphate was 1.25 mmol/L (3.87 mg/dl), mean pulse wave velocity was 10.8 m/s, and 81.3% had abdominal aortic calcification at baseline. At 96 weeks, pulse wave velocity did not differ significantly between groups, nor did abdominal aortic calcification, serum phosphate, parathyroid hormone, FGF23, and 24-hour urinary phosphate. Serious adverse events occurred in 63 (46%) participants prescribed lanthanum and 66 (47%) prescribed placebo. Although recruitment to target was not achieved, additional analysis suggested this was unlikely to have significantly affected the principle findings.CONCLUSIONS:In patients with stage 3b/4 CKD, treatment with lanthanum over 96 weeks did not affect arterial stiffness or aortic calcification compared with placebo. These findings do not support the role of intestinal phosphate binders to reduce cardiovascular risk in patients with CKD who have normophosphatemia.CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER:Australian Clinical Trials Registry, ACTRN12610000650099.

Objectives We sought to assess the validity of the DILEMMA score against instantaneous wave-free ratio (iFR) and evaluate its utility in rationalizing the number of patients referred for invasive physiological assessment. Background The DILEMMA score is a validated angiographic scoring tool incorporating minimal lumen diameter, lesion length and subtended myocardial area that has been shown to predict the functional significance of lesions as assessed by fractional flow reserve (FFR). Methods Patients in the DEFINE-FLAIR study who had coronary stenosis of intermediate severity were randomized to either FFR or iFR. DILEMMA score was calculated retrospectively on a subset of this cohort by operators blinded to FFR or iFR values. Results Three hundred and forty-six lesions (181 assessed by FFR; 165 by iFR) from 259 patients (mean age 66.0 years, 79% male) were included. A DILEMMA score <= 2 had a negative predictive value of 96.3% and 95.7% for identifying lesions with FFR >0.80 and iFR >0.89, respectively. A DILEMMA score >= 9 had a positive predictive value of 88.9% and 100% for identifying lesions with FFR <= 0.80 and iFR <= 0.89, respectively. The receiver operating characteristic area under the curve values for DILEMMA score to predict FFR <= 0.80 and iFR <= 0.89 were 0.83 (95% CI 0.77-0.90) and 0.82 (0.75-0.89) respectively. A DILEMMA score <= 2 or >= 9 occurred in 172 of the 346 lesions (49.7%). Conclusions Using DILEMMA score in patients with coronary stenosis of intermediate severity may reduce the need for pressure wire use, offering potential cost-savings and minimizing the risks associated with invasive physiological lesion assessment.

BACKGROUND The left internal mammary artery（LIMA） has demonstrated excellent long-term patency rates when used as a bypass conduit with complications usually occurring in the early postoperative period. The rapid development of de-novo atherosclerosis in a previously non-diseased LIMA, subsequently leading to an acute coronary syndrome（ACS） is rarely encountered.CASE SUMMARY A 67-year-old man with history of triple coronary artery bypass graft（8 years ago） presented to our hospital with an ACS. He had undergone angiography 5 years ago to investigate episodic chest pain and imaging of the LIMA at the time did not demonstrate the atherosclerotic process. Emergent angiography demonstrated a severe diffuse stenosis in the proximal to mid segment of the LIMA, with embolization of a moderate sized thrombus to the distal skip segment. The LIMA stenosis was characterised by overlying haziness, consistent with acute plaque rupture, associated with residual luminal thrombus. The patient was managed with antithrombotic therapy to reduce the thrombus burden until repeat angiography after 72 h. At repeat angiography, the thrombus burden was substantially reduced at the distal skip segment as well as at the proximal to mid LIMA with the demonstration of multiple plaque cavities. This lesion was predilated and a 2.75 mm × 33 mm everolimus-eluting stent was implanted to a final diameter of 3.0 mm. The patient made a good clinical recovery and was discharged after 6 d.CONCLUSION This case highlights the rapid and late development of atherosclerosis in a graft 5 years after documented patency and the importance for consideration of expectant thrombus management.

Background: Primary aldosteronism (PA) has a reported prevalence of up to 30% in cases of resistant hypertension and is associated with worse cardiovascular outcomes than BP-matched essential hypertension (EH), but is substantially under-diagnosed due to the lack of specific symptoms and signs. Ambulatory blood pressure monitoring (ABPM) provides a non-invasive method for evaluating circadian BP variations, offers valuable prognostic information and may help to differentiate PA from EH in patients referred with non-specific hypertension for investigation. Aims: To compare AMBP parameters in hypertensive patients with established PA and those without, and correlate these parameters with cardiovascular outcomes. Methods: AMBP readings were evaluated retrospectively in 453 patients assessed at Monash Heart (the largest cardiology service in Victoria, Australia). Patient demographics, screening aldosterone and renin concentrations and medications were retrieved from medical records. 414 hypertensive patients with presumed EH and 39 PA patients were identified and their cardiovascular events (myocardial infarction, left ventricular hypertrophy, coronary artery disease, atrial fibrillation) were recorded. All parameters are reported as the median [interquartile range], unless stated otherwise. Statistical significance was set at p<0.05. Results: Compared to hypertensive patients who are presumed to have EH, PA patients were significantly younger (55 yr [50, 66] vs 63 yr [53, 72]), had higher systolic (149 mmHg [134, 156] vs 133 mmHg [124, 145]) and diastolic BP readings (87 mmHg [82, 92] vs 75 mmHg [68, 82]) with similar patterns observed for average daytime and night-time BP. BP load (% daytime and night-time SBP/DBP readings over 135/85 and 120/70 mmHg, respectively) was significantly higher for both systolic and diastolic in PA (83% [61, 92] and 57% [35, 76]) compared with the non-PA group (48% [23, 75] and 14% [5, 35]). 77% of patients with PA (30/39) had loss of physiological nocturnal BP dipping compared with 44% of the non-PA group (184/414). Rates of cardiovascular events were similar in both groups but may be confounded by the retrospective nature of this study and lack of long-term follow-up. Conclusion: In our study, PA is associated with a distinctive 24-hour BP profile, including a significant increase in BP load and loss of nocturnal BP dipping which are known risk factors for adverse cardiovascular events. A prospective study is needed to better define AMBP parameters in PA and evaluate their ability to unveil underlying PA amongst hypertensive patients.

Objectives: Primary aldosteronism (PA) has a reported prevalence of up to 30% in cases of resistant hypertension, but is substantially under-diagnosed due to the lack of specific symptoms and signs. Ambulatory blood pressure monitoring (ABPM) provides a non-invasive method for evaluating circadian BP variations and may help to identify PA in patients with non-specific hypertension for investigation. We set out to compare ABPM parameters in hypertensive patients with established PA and those without, and correlate these parameters with cardiovascular outcomes. Methods: ABPM readings were evaluated retrospectively in 407 patients assessed at Monash Heart (the largest cardiology service in Victoria, Australia). 396 non-PA and 11 PA patients were identified and their cardiovascular events were recorded. Statistical significance was set at p < 0.05. Results: Compared to hypertensive patients without established PA, PA patients were younger (mean: 51.5 ± 13.3 vs 62.2 ± 14.2 years) and had higher BP readings (mean: 150/86 ± 20.5/7.4 vs 134/75 ± 17.2/10.7 mmHg). BP load was significantly higher for both systolic and diastolic in PA (mean: 72.4 ± 26.4 and 50.2 ± 25.6 %) compared with the non-PA group (mean: 49.3 ± 28.5 and 21.6 ± 22.7 %). 81% of patients with PA (9/11) had loss of physiological nocturnal BP dipping compared with 44% of the non-PA group (175/396). Rates of cardiovascular events were similar in both groups but may be confounded by the lack of long-term follow-up. Conclusion: In our study, PA is associated with a significant increase in BP load and loss of nocturnal BP dipping which are known risk factors for adverse cardiovascular events.

The correspondents are incorrect in saying that no statistical tests are reported – the results of linear mixed model analyses are given in Tables 3–5 and shown in Fig. 3. We have, however, in accordance with recent statistical guidelines, not presented P values . On the basis of these data, there is no convincing evidence that the within-individual variability of reservoir pressure and measured pressure differ. For example, the intraclass correlation coefficient (ICC, a measure of within-individual similarity between sites) for maximum P r – diastolic pressure (Table 5) is 0.98 [95% confidence interval (CI) 0.96–0.99], whereas for SBP (Table 3), it is 0.96 (95% CI 0.94–0.98; 95% CIs of the ICCs were omitted from the original tables because of space limitations).

DILEMMA score is a validated angiographic scoring tool incorporating minimal lumen diameter, lesion length and subtended myocardial area and can be used to reliably exclude lesions which have a predictably high likelihood of being functionally significant or non-significant as assessed by FFR. We

The significance of coronary artery disease (CAD) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) remains unclear. Previous studies using angiographic scoring systems (e.g. SYNTAX score) have produced conflicting results, but these algorithms do

OBJECTIVES:A reservoir pressure model describing left ventricular-large artery interaction has been proposed as a useful heuristic model providing insight into the propagation of the central blood pressure as well as providing clinical prognostic information. A pressure-only approach to calculation of reservoir pressure waves has been proposed but this assumes that the resultant excess pressure is proportional to the volume flow rate out of the left ventricle; this has not been tested in humans. APPROACH:We use non-invasively acquired central pressure and flow data obtained in the 2nd Australian National Blood Pressure Study to test this assumption and to investigate the use of flow approximations based on excess pressure or an assumed triangular flow pattern in calculation of forward and backwards waves in the aortic root. MAIN RESULTS:Results from 821 subjects showed close association between the shape of measured flow patterns and calculated excess pressure, with mean coefficient of determination R 2  =  0.931  ±  0.046(SD). For directly measured versus triangular flow approximation R 2 was 0.918  ±  0.057. Comparison of the peak amplitudes of forwards (Pf) and backwards (Pb) going pressure waves resulted in significant correlation between Pfmax and Pbmax using both measured flow and the triangular flow approximation (0.83 and 0.79 respectively) and using excess pressure as a flow approximation (Pfmax 0.86 and Pbmax 0.77). All associations for peak pressures and integrals were high with R-values between 0.70 and 0.95. SIGNIFICANCE:Pressure-only reservoir wave analysis appears to conform to the inherent assumptions underpinning the mathematical approach employed: this provides support for use of reservoir analysis as a non-invasive method to describe potentially important features and functions of ventriculo-vascular interaction without the requirement for flow measurement.

BACKGROUND:Stenotic flow reserve (SFR) derived from quantitative coronary angiography (QCA) has been correlated with myocardial ischaemia as determined by pharmacological stress echocardiography. However, the diagnostic accuracy of SFR in predicting functionally significant coronary stenosis as assessed by the gold standard, fractional flow reserve (FFR), has not been previously characterised. METHODS:Patients who underwent coronary angiography and FFR assessment between January 2010 and February 2012 in a single tertiary centre were retrospectively assessed. QCA parameters such as minimal lumen diameter (MLD), lesion length, diameter stenosis (DS), SFR, turbulent resistance (TR) and Poiseuille resistance (PR) were assessed. Significant FFR was defined as FFR ≤0.8. The diagnostic accuracy of QCA parameters to predict significant FFR was assessed by independent t-test and receiver operator characteristic (ROC) curve. Statistical significance was defined as P value of <0.05. RESULTS:The study included 272 patients (age: 64±11, 70% males) and 415 vessels. There were 180 (43%) vessels which were FFR significant. The mean FFR value for all vessels was 0.81±0.11. On comparison of AUC for predicting significant FFR, SFR (AUC =0.76) had the highest diagnostic accuracy compared to PR (AUC =0.75), % DS (AUC =0.73), TR (AUC =0.69), MLD (AUC =0.71) and DS >50% (AUC =0.64). Using a retrospectively determined optimal cut-off value of 3.51, the sensitivity of stenotic-flow-reserve was modest at 56% with good specificity of 81%. DS >50% had a sensitivity of 47% and specificity of 82% in predicting significant FFR. There was incremental predictive value when SFR was added to DS >50% on integrated discrimination improvement index (IDI =0.103, P<0.001) and net reclassification index (NRI =0.72, P<0.001). CONCLUSIONS:SFR has modest diagnostic accuracy for predicting significant FFR but adds incremental predictive value to DS >50% for predicting significant FFR.