Role of anatomical regurgitant orifice area and right ventricular contractile reserve in severe tricuspid regurgitation.

AIMS: We sought to propose a novel risk stratification system for severe tricuspid regurgitation (TR) using 3D-anatomical regurgitant orifice area (3D-AROA) and the slope of tricuspid annular plane systolic excursion vs. systolic pulmonary artery pressure (TAPSE/SPAP) and to validate its prognostic significance. METHODS AND RESULTS: Sixty-four patients with severe functional TR (52% torrential) underwent 3D echocardiography and exercise-stress echocardiography. As an estimate of regurgitation severity, 3D-AROA was measured with the customized software package. As an index of right ventricular (RV) contractile reserve, the TAPSE/SPAP slope was calculated by plotting the relationship between TAPSE and SPAP during exercise test. Haemodynamic parameters were obtained by right heart catheterization (RHC). Based on receiver operating characteristics curves, optimal cut-off values of 3D-AROA and TAPSE/SPAP slope to identify all-cause mortality were 161 mm2 and 0.046 mm/mmHg, respectively. During a median follow-up of 559 days, 20 patients (31%) died. After correcting for potential confounders, 3DAROA≥ 161 mm2 (HR 4.37; 95% CI 1.34-14.07; P = 0.015) and TAPSE/SPAP slope≤0.046 mm/mmHg (HR 4.76; 95% CI 1.46-15.53; P = 0.009) were echocardiographic parameters independently associated with all-cause mortality. The cumulative survival rate was lower in patients with 3D-AROA≥161 mm2 and TAPSE/SPAP slope≤0.046 mm/mmHg compared with their counterparts (both P<0.05). RHC confirmed higher right atrial pressure (P<0.001) and lower cardiac index (P = 0.004) in patients with both 3D-AROA≥161 mm2 and TAPSE/SPAP slope ≤0.046 mm/mmHg. CONCLUSION: Large AROA and reduced RV contractile reserve during exercise are independently associated with poor prognosis. The new grading scheme of severe TR was validated by haemodynamics and may improve risk stratification.

Effects of aging on coronary flow reserve in patients with no evidence of myocardial perfusion abnormality.

Coronary flow reserve (CFR) reflects the functional capacity of microcirculation to adapt to blood demand during increased cardiac work. We tested the hypothesis that aging had impacts on coronary flow velocities and CFR in patients with no evidence of myocardial perfusion abnormality on single photon emission computed tomography (SPECT). Seventy-six patients undergoing transthoracic Doppler echocardiography with no evidence of myocardial perfusion abnormality on SPECT were enrolled in this study. CFR was defined as the ratio of hyperemic to resting peak diastolic coronary flow velocity. Patients were divided into the three groups based on age: 17 patients aged less than 70 years (Group I), 38 patients aged 70-79 years (Group II), and 21 patients aged 80 years or more (Group III). Compared with Group I, CFR was significantly lower in Group II (p < 0.01) and Group III (p < 0.01). Multivariate linear regression analysis showed that female (ß = - 0.26, p = 0.03), cigarette smoking (ß = - 0.32, p = 0.004), hemoglobin level (ß = - 0.40, p = 0.001) and LV mass index (ß = 0.24, p = 0.03) were determinants for resting coronary flow velocity. On the other hand, age (ß = -0.30, p = 0.008), hemoglobin level (ß = -0.47, p < 0.001) and LV mass index (ß = 0.24, p = 0.04) were determinants for hyperemic coronary flow velocity. Age was only determinant for CFR (ß = -0.48, p < 0.001). Our data suggested that that aging had a decreased effect on hyperemic coronary flow velocity rather than resting coronary flow velocity, and was further associated with impaired CFR in patients with no evidence of myocardial perfusion abnormality.