Blood flow dynamics with four-dimensional flow cardiovascular magnetic resonance in patients with aortic stenosis before and after transcatheter aortic valve replacement.

BACKGROUND: Pre- and post-procedural hemodynamic changes which could affect adverse outcomes in aortic stenosis (AS) patients who undergo transcatheter aortic valve replacement (TAVR) have not been well investigated. Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) enables accurate analysis of blood flow dynamics such as flow velocity, flow pattern, wall shear stress (WSS), and energy loss (EL). We sought to examine the changes in blood flow dynamics of patients with severe AS who underwent TAVR. METHODS: We examined 32 consecutive severe AS patients who underwent TAVR between May 2018 and June 2019 (17 men, 82 ± 5 years, median left ventricular ejection fraction 61%, 6 self-expanding valve), after excluding those without CMR because of a contraindication or inadequate imaging from the analyses. We analyzed blood flow patterns, WSS and EL in the ascending aorta (AAo), and those changes before and after TAVR using 4D flow CMR. RESULTS: After TAVR, semi-quantified helical flow in the AAo was significantly decreased (1.4 ± 0.6 vs. 1.9 ± 0.8, P = 0.002), whereas vortical flow and eccentricity showed no significant changes. WSS along the ascending aortic circumference was significantly decreased in the left (P = 0.038) and left anterior (P = 0.033) wall at the basal level, right posterior (P = 0.011) and left (P = 0.010) wall at the middle level, and right (P = 0.012), left posterior (P = 0.019) and left anterior (P = 0.028) wall at the upper level. EL in the AAo was significantly decreased (15.6 [10.8-25.1 vs. 25.8 [18.6-36.2]] mW, P = 0.012). Furthermore, a significant negative correlation was observed between EL and effective orifice area index after TAVR (r = - 0.38, P = 0.034). CONCLUSIONS: In severe AS patients undergoing TAVR, 4D flow CMR demonstrates that TAVR improves blood flow dynamics, especially when a larger effective orifice area index is obtained.

Significance and prognostic impact of v wave on pulmonary artery pressure in patients with heart failure: beyond the wedge pressure.

BACKGROUND: A v wave on pulmonary artery wedge (PAW) pressure sometimes augments and appears on pulmonary artery (PA) pressure wave in patients with heart failure (HF). However, the significance of PA v wave in HF remains to be elucidated. METHODS: We retrospectively analyzed pressure waveforms in 61 HF patients (left ventricular ejection fraction 35 ± 15%). On the PAW and PA pressure waveforms, mean pressure as well as peak and amplitude of v waves (ampPAWv and ampPAv, respectively) were measured. Occurrence of worsening HF and cardiac death was recorded for 2 years after the catheterization. RESULTS: The ampPAWv did not correlate with ampPAv. When the patients were divided into 4 groups: I (high-ampPAWv/high-ampPAv), II (high-ampPAWv/low-ampPAv), III (low-ampPAWv/high-ampPAv), and IV (low-ampPAWv/low-ampPAv), the prevalence of group III was low (I: 13, II: 17, III: 4, IV: 27). Mean pressures of PAW and PA were similarly elevated in groups I and II. Cardiac index was lowest (I: 2.0 ± 0.4, II: 2.8 ± 0.6, III: 2.2 ± 0.2, IV: 2.4 ± 0.6 L/min/m2, ANOVA P < 0.01, P < 0.01 for I vs II) and tricuspid annular plane systolic excursion / systolic PA pressure was impaired (I: 0.27 ± 0.07, II: 0.48 ± 0.22, III: 0.59 ± 0.35, IV: 0.68 ± 0.35 mm/mmHg, ANOVA P < 0.01) in group I. During the follow-up, 13 events were observed. Kaplan-Meier analysis showed that patients in group I were at highest risk of cardiac events. CONCLUSIONS: PA v was observed mainly in patients with augmented PAW v wave and decreased cardiac index, suggesting an advanced stage of HF. Moreover, augmented PAv was associated with worse outcome in HF patients.

Diastolic Intra-Left Ventricular Pressure Difference During Exercise: Strong Determinant and Predictor of Exercise Capacity in Patients With Heart Failure.

BACKGROUND: Although the enhancement of early-diastolic intra-left ventricular pressure difference (IVPD) during exercise is considered to maintain exercise capacity, little is known about their relationship in heart failure (HF). METHODS AND RESULTS: Cardiopulmonary exercise testing and exercise-stress echocardiography were performed in 50 HF patients (left ventricular [LV] ejection fraction 39 ± 15%). Echocardiographic images were obtained at rest and submaximal and peak exercise. Color M-mode Doppler images of LV inflow were used to determine IVPD. Thirty-five patients had preserved exercise capacity (peak oxygen consumption [VO2] ≥14 mL·kg-1·min-1; group 1) and 15 patients had reduced exercise capacity (group 2). During exercise, IVPD increased only in group 1 (group 1: 1.9 ± 0.9 mm Hg at rest, 4.1 ± 2.0 mm Hg at submaximum, 4.7 ± 2.1 mm Hg at peak; group 2: 1.9 ± 0.8 mm Hg at rest, 2.1 ± 0.9 mm Hg at submaximum, 2.1 ± 0.9 mm Hg at peak). Submaximal IVPD (r = 0.54) and peak IVPD (r = 0.69) were significantly correlated with peak VO2. Peak IVPD determined peak VO2 independently of LV ejection fraction. Moreover, submaximal IVPD could well predict the reduced exercise capacity. CONCLUSION: Early-diastolic IVPD during exercise was closely associated with exercise capacity in HF. In addition, submaximal IVPD could be a useful predictor of exercise capacity without peak exercise in HF patients.

Tricuspid regurgitation occurring in the early-diastolic phase in a case of heart failure: Insights from echocardiographic and invasive hemodynamic findings.

Although the presence and physiological significance of late-diastolic tricuspid regurgitation (TR) have been reported, those in TR occurring in early diastole have not been well known. We herein first presented a case of heart failure due to dilated cardiomyopathy showing functional TR occurring in the early-diastolic phase in whom the mechanism for its genesis could be precisely assessed from echocardiographic findings and intra-cardiac pressure recordings.

Influence of advanced pulmonary vascular remodeling on accuracy of echocardiographic parameters of left ventricular filling pressure.

Evaluation of left ventricular filling pressure plays an important role in the clinical management of pulmonary hypertension. However, the accuracy of echocardiographic parameters for the determination of left ventricular filling pressure in the presence of pulmonary vascular lesions has not been fully addressed. We retrospectively investigated 124 patients with pulmonary hypertension due to pulmonary vascular lesions (noncardiac pulmonary hypertension group) and 113 patients with ischemic heart disease (control group) who underwent right heart catheterization and echocardiography. The noncardiac pulmonary hypertension group was subdivided into less-advanced and advanced groups according to median pulmonary vascular resistance. Pulmonary artery wedge pressure was determined as left ventricular filling pressure. As echocardiographic parameters of left ventricular filling pressure, the ratio of early- (E) to late-diastolic transmitral flow velocity (E/A), ratio of E to early-diastolic mitral annular velocity (E/e'), and left atrial volume index were measured. In the less-advanced noncardiac pulmonary hypertension and control groups, positive correlations were observed between pulmonary artery wedge pressure and late-diastolic transmitral flow velocity (R = 0.41, P = 0.002 and R = 0.71, P < 0.001, respectively) and left atrial volume index (R = 0.53, P < 0.001 and R = 0.41, P < 0.001), whereas in the advanced noncardiac pulmonary hypertension group, pulmonary artery wedge pressure was only correlated with left atrial volume index (R = 0.27, P = 0.032). In the controls, only pulmonary artery wedge pressure determined E (ß = 0.48, P < 0.001), whereas both pulmonary artery wedge pressure and pulmonary vascular resistance were independent determinants of E (ß = 0.29, P < 0.001 and ß = -0.28, P = 0.001, respectively) in the noncardiac pulmonary hypertension group. In conclusion, in the presence of advanced pulmonary vascular lesions, conventional echocardiographic parameters may not accurately reflect left ventricular filling pressure. Elevated pulmonary vascular resistance would lower the E, even when pulmonary artery wedge pressure is elevated, resulting in blunting of echocardiographic parameters for the detection of elevated left ventricular filling pressure.

Simple Two-Dimensional Echocardiographic Scoring System for the Estimation of Left Ventricular Filling Pressure.

BACKGROUND: When left ventricular filling pressure (LVFP) increases, the mitral valve opens early and precedes tricuspid valve opening in early diastole. The authors hypothesized that a visually assessed time sequence of atrioventricular valve opening could become a new marker of elevated LVFP. The aim of this study was to test the diagnostic ability of a novel echocardiographic scoring system, the visually assessed time difference between mitral valve and tricuspid valve opening (VMT) score, in patients with heart failure. METHODS: One hundred nineteen consecutive patients who underwent cardiac catheterization within 24 hours of echocardiographic examination were retrospectively analyzed as a derivation cohort. In addition, a prospective study was conducted to validate the diagnostic ability of the VMT score in 50 patients. Elevated LVFP was defined as mean pulmonary artery wedge pressure (PAWP) ≥ 15 mm Hg. The time sequence of atrioventricular valve opening was visually assessed and scored (0 = tricuspid valve first, 1 = simultaneous, 2 = mitral valve first). When the inferior vena cava was dilated, 1 point was added, and VMT score was ultimately graded as 0 to 3. Cardiac events were recorded for 1 year after echocardiography. RESULTS: In the derivation cohort, PAWP was elevated with higher VMT scores (score 0, 10 ± 5; score 1, 12 ± 4; score 2, 22 ± 8; score 3, 28 ± 4 mm Hg; P < .001, analysis of variance). VMT score ≥ 2 predicted elevated PAWP with accuracy of 86% and showed incremental predictive value over clinical variables and guideline-recommended diastolic function grading. These observations were confirmed in the prospective validation cohort. Importantly, VMT score ≥ 2 discriminated elevated PAWP with accuracy of 82% in 33 patients with monophasic left ventricular inflow in the derivation cohort. Kaplan-Meier analysis demonstrated that patients with VMT scores ≥ 2 were at higher risk for cardiac events than those with VMT scores ≤ 1 (P < .001). CONCLUSIONS: VMT scoring could be a novel additive marker of elevated LVFP and might also be associated with adverse outcomes in patients with heart failure.

Acute Myocardial Infarction of the Left Main Coronary Artery Presenting with Cardiogenic Shock and Pulmonary Edema during Noncardiac Surgery.

Acute myocardial infarction (AMI) caused by severe stenosis of left main coronary artery (LMCA) presenting with cardiogenic shock and pulmonary edema during noncardiac surgery is uncommon, but a catastrophic event. A 77-year-old male with cholangiocarcinoma underwent hepatectomy. During the surgery, he presented with cardiogenic shock, which did not respond to infusion administration or vasopressor. A transesophageal echocardiogram revealed anterior, septal, and lateral severe hypokinesia and impaired left ventricular function. Emergent coronary angiogram showed severe stenosis of LMCA. The patient underwent primary percutaneous coronary intervention (PCI) under the support of intra-aortic balloon pump, followed by extracorporeal membrane oxygenation. The chest roentgenogram showed pulmonary edema. Two days after PCI, he successfully underwent hepatectomy and bile duct resection. Early identification of the cause of hemodynamic instability during noncardiac surgery and invasive strategy are important for minimizing the myocardial injury and improving clinical outcomes in AMI of LMCA.

Heart Failure With Preserved Ejection Fraction vs. Reduced Ejection Fraction　- Mechanisms of Ventilatory Inefficiency During Exercise in Heart Failure.

Background: Ventilatory inefficiency during exercise assessed using the lowest minute ventilation/carbon dioxide production (V̇E/V̇CO2) ratio was recently proven to be a strong prognostic marker of heart failure (HF) regardless of left ventricular ejection fraction (LVEF). Its physiological background, however, has not been elucidated. Methods and Results: Fifty-seven HF patients underwent cardiopulmonary exercise testing and exercise-stress echocardiography. The lowest V̇E/V̇CO2 ratio was assessed on respiratory gas analysis. Echocardiography was obtained at rest and at peak exercise. LVEF was measured using the method of disks. Cardiac output (CO) and the ratio of transmitral early filling velocity (E) to early diastolic tissue velocity (e') were calculated using the Doppler method. HF patients were divided into preserved EF (HFpEF) and reduced EF (HFrEF) using the LVEF cut-off 40% at rest. Twenty-four patients were classified as HFpEF and 33 as HFrEF. In HFpEF, age (r=0.58), CO (r=-0.44), e' (r=-0.48) and E/e' (r=0.45) during exercise correlated with the lowest V̇E/V̇CO2 ratio (P<0.05 for all). In contrast, in HFrEF, age (r=0.47) and CO (r=-0.54) during exercise, but not e' and E/e', correlated with the lowest V̇E/V̇CO2 ratio. Conclusions: Loss of CO augmentation was associated with ventilatory inefficiency in HF regardless of LVEF, although lung congestion determined ventilatory efficiency only in HFpEF.

Reversible Cancer Therapeutics-related Cardiac Dysfunction Complicating Intra-cardiac Thrombi.

Epirubicin-based chemotherapy carries a risk of inducing heart failure, although the frequency is rare. Bevacizumab, an anti-vascular endothelial growth factor monoclonal antibody, has recently been widely used in patients with recurrent breast cancer as a first-line chemotherapeutic agent. Heart failure or arterial thromboembolism has been reported as a rare cardiovascular complication of bevacizumab. We herein report a breast cancer patient with reversible cancer therapeutics-related cardiac dysfunction associated with bevacizumab and epirubicin complicating intracardiac thrombi in the left atrium and left ventricle. This case underscores the importance of tailored medical planning according to the individual status in patients receiving anti-cancer therapies.

Simple and noninvasive method to estimate right ventricular operating stiffness based on echocardiographic pulmonary regurgitant velocity and tricuspid annular plane movement measurements during atrial contraction.

It was recently shown that invasively determined right ventricular (RV) stiffness was more closely related to the prognosis of patients with pulmonary hypertension than RV systolic function. So far, a completely noninvasive method to access RV stiffness has not been reported. We aimed to clarify the clinical usefulness of our new echocardiographic index of RV operating stiffness using atrial-systolic descent of the pulmonary artery-RV pressure gradient derived from pulmonary regurgitant velocity (PRPGDAC) and tricuspid annular plane movement during atrial contraction (TAPMAC). We studied 81 consecutive patients with various cardiac diseases who underwent echocardiography and cardiac catheterization. We measured PRPGDAC and TAPMAC using continuous-wave Doppler and M-mode echocardiography, respectively, and calculated PRPGDAC/TAPMAC. RV end-diastolic pressure (RVEDP) and RV pressure increase during atrial contraction (ΔRVPAC) were invasively measured, and RV volume change during atrial contraction (ΔVAC) was calculated from echocardiographic late-diastolic transtricuspid flow time-velocity integral and tricuspid annular area; thus ΔRVPAC/ΔVAC was used as the standard index for RV operating stiffness. PRPGDAC/TAPMAC well correlated with ΔRVPAC/ΔVAC (r = 0.84, p < 0.001) and RVEDP (r = 0.80, p < 0.001), and the area under the receiver operating characteristic curve to discriminate RVEDP > 12 mmHg was 0.94. Multivariate regression analysis revealed that PRPGDAC/TAPMAC was the single independent determinant of ΔRVPAC/ΔVAC (ß = 0.86, p < 0.001). PRPGDAC/TAPMAC is useful to estimate RV operating stiffness and a good practical indicator of RVEDP.