Arterial stiffness and mitral regurgitation in arterial hypertension: an intriguing pathophysiological link

Background: We examined the relative impact of arterial stiffness on the presence and/or severity of chronic mitral regurgitation (MR) in hypertensive patients. Methods: We prospectively enrolled 141 untreated hypertensive patients (mean age 56.6 ± 11.5 years): 94 with MR, 47 without MR. As a measure of arterial stiffness, pulse wave velocity (PWV) was assessed by applanation tonometry. Assessment of MR severity was obtained through calculation of effective regurgitant orifice area (EROA) and vena contracta by standard two-dimensional transthoracic echocardiography. Results: PWV appears to progressively increase according to the presence and severity of MR (no MR = 7.3 ± 1.1 m/s, mild MR = 7.9 ± 1.3 m/s, moderate MR = 9.0 ± 1.7 m/s, severe MR = 13.3 ± 4.1 m/s; P < 0.001 for all comparisons). EROA was positively correlated with age (P = 0.011), left atrial volume index (P = 0.023), PWV (P < 0.001) and augmentation index (P < 0.001), and negatively correlated with left ventricular ejection fraction (P = 0.002) and heart rate (HR) (P = 0.018). On stepwise multivariate logistic regression analysis, only PWV (OR = 2.87, 95% CI 1.750–4.738, P < 0.001) and HR (OR = 0.94, 95% CI 0.895–0.994, P = 0.02) appeared to be independent predictors of severe MR. Receiver operating characteristic curves showed that a cutoff of 9 m/s for PWV provided the best sensitivity/specificity for predicting both the presence of any degree of MR (sensitivity 73%, specificity 87%, AUC = 0.863; P < 0.001) and MR severity (sensitivity 100%, specificity 81%, AUC = 0.954; P < 0.001). Conclusion: Reduced arterial elasticity because of increased stiffness may be an important marker for the presence and severity of MR in hypertensive patients.