Cardiovascular Risk Calculators and their Applicability to South Asians.

BACKGROUND: Estimation of absolute cardiovascular disease (CVD) risk and tailoring therapies according to the estimated risk is a fundamental concept in the primary prevention of CVD is assessed in this study. Numerous CVD risk scores are currently available for use in various populations but unfortunately, none exist for South Asians who have much higher CVD risk as compared to their western counterparts. METHODS: A literature search was done using PubMed and Google search engines to prepare a narrative review on this topic. RESULTS: Various currently available CVD risk scores and their pros and cons are summarized. The studies performed in native as well as migrant South Asians evaluating the accuracy of these risk scores for estimation of CVD risk are also summarized. The findings of these studies have generally been inconsistent, but it appears that the British risk scores (e.g. QRISK versions) may be more accurate because of inclusion of migrant South Asians in the derivation of these risk scores. However, the lack of any prospective study precludes our ability to draw any firm conclusions. Finally, the potential solution to these challenges, including the role of recalibration and subclinical atherosclerosis imaging, is also discussed. CONCLUSION: This review highlights the need to develop large, representative, prospectively followed databases of South Asians providing information on various CVD risk factors and their contribution to incident CVD. Such databases will not only allow the development of validated CVD risk scores for South Asians but will also enable application of machine-learning approaches to provide personalized solutions to CVD risk assessment and management in these populations.

Aortic pulse wave velocity and its relationship with transaortic flow and gradients in patients with severe aortic stenosis undergoing aortic valve replacement.

BACKGROUND: Low-flow, low-gradient severe aortic stenosis (LFLGAS) is a common clinical entity and is associated with poor prognosis. Increased left ventricular (LV) afterload is one of the mechanisms contributing to low LV stroke volume index (SVi) in these patients. Aortic stiffness is an important determinant of LV afterload, but no previous study has evaluated its relationship with LVSVi in patients with AS. METHODS: Fifty-seven patients (mean age 66 ± 8 years, 71.9% men) with severe AS [aortic valve area (AVA) < 1.0 cm2] undergoing aortic valve replacement (AVR) were included in this study. Echocardiographic parameters of AS were correlated with carotid-femoral pulse wave velocity (cfPWV), a measure of aortic stiffness, derived using PeriScope® device. RESULTS: Mean AVA was 0.63 ± 0.17 cm2 with mean and peak transvalvular gradient 56.5 ± 18.8 mmHg and 83.2 ± 25.2 mmHg, respectively. Nearly half (26 of 57, 45.6%) of the subjects had SVi <35 mL/m2, indicative of low-flow severe AS. These subjects had lower AVA, lower aortic valve gradient, and LV ejection fraction. CfPWV was numerically lower in these subjects [median 1467 (interquartile range 978, 2259) vs 1588 (1106, 2167)] but the difference was not statistically significant (p = 0.66). However, when analyzed as a continuous variable, cfPWV had significant positive correlation with SVi (Pearson's r 0.268, p = 0.048) and mean aortic valve gradient (Pearson's r 0.274, p = 0.043). CONCLUSIONS: In patients with severe AS undergoing AVR, aortic stiffness measured using cfPWV is not a determinant of low-flow state. Instead, an increasing cfPWV tends to be associated with increasing transvalvular flow and gradient in these patients.