Noninvasive Assessment of the Right Ventricular Filling Pressure Gradient

Abstract

Background-The physiological basis of right ventricular (RV) diastolic function remains incompletely studied in humans.The driving force responsible for RV filling, the pressure gradient along the RV inlet from the right atrium to the RV apex, has never been measured in the clinical setting. Methods and Results-We validated a method for measuring the RV filling pressure difference (RVFPD) from color Doppler M-mode recordings in 12 pigs undergoing interventions on RV preload, afterload, and lusitropic states (error, Ϫ0.1Ϯ0.4 mm Hg compared with micromanometers; intraclass correlation coefficient, 0.88). Peak early RVFPD correlated directly with mean right atrial pressure and inversely with the time constant of RV relaxation. In 21 patients with dilated cardiomyopathy, the peak RVFPD was 1.0 mm Hg (95% CI, 0.8 to 1.2), significantly lower than in age-matched control subjects (1.4 mm Hg; 95% CI, 1.2 to 1.6). In another population of 19 young healthy volunteers, the peak RVFPD was 2.3 mm Hg (95% CI, 2.0 to 2.6), which was reduced by nitroglycerine and esmolol and was augmented by volume overload and atropine infusions. RVFPD was generated almost exclusively by inertial forces. Conclusions-For the first time, the RV driving filling force can be accurately measured noninvasively in the clinical setting, and the method is sensitive to detect the effects of preload, chronotropic, and lusitropic states. In patients with dilated cardiomyopathy, the RV filling force is markedly reduced, indicating severely impaired RV relaxation. These findings suggest that this is a useful tool for improving the clinical assessment of RV diastolic function. (Circulation.

Abnormal Right Ventricular Relaxation in Pulmonary Hypertension

“…32 A noninvasive study has also suggested the presence of a diastolic filling gradient in humans. 33 A major caveat to the above is that we do not have data on diastolic stiffness or RV volume for our patients. Further study is needed to clarify the relative impact on RV filling pressures of changes in these factors versus active relaxation.…”

Prognostic significance of the right ventricular function in patients with CHF

“…В этом плане привлекательно выглядит оценка диастолической функции ПЖ, которая, с одной стороны, является марке-ром ранней или скрытой дисфункции ПЖ [7,8], а с дру-гой -также может иметь независимое прогностическое значение [9]. Работы последних лет показали, что оцен-ка диастолической функции ЛЖ может проводиться с помощью различных показателей как на основе анали-за транстрикуспидальных потоков и распространения их в полости ПЖ, так и движения стенок ПЖ [10,11]. Показано, что они могут иметь различное клиническое значение в выявлении нарушений наполнения ПЖ [12], однако их относительное прогностическое значение пока мало изучено.…”

“…При определении этого показа-теля в режиме непрерывно-волновой допплерометрии отмечалось увеличение риска смерти в 1,3 раза при его увеличении на 0,1 [23]. С появлением спектральной тка-невой допплерометрии определение индекса Теи ПЖ значительно упростилось, а его определение было вклю-чено в необходимый минимум рекомендованных пока-зателей функции ПЖ [10]. Информативность индекса Теи подтверждается и в ходе контроля за результатами тромбэндартерэктомии [24] и митральной комиссу-ротомии [25].…”

Nonconvective Forces: A Critical and Often Ignored Component in the Echocardiographic Assessment of Transvalvular Pressure Gradients

“…While these experiments demonstrate the role of nonconvective, or inertial, forces for transmitral flow, it is important to consider that the same principles apply for other applications that measure pressure gradients within the heart, such as intraventricular pressure gradients [16, 17], right ventricular filling pressures [18], intracardiac shunts, and pulmonary hypertension [19]. For example, while Doppler velocities are routinely used to derive pulmonary artery pressures [20], it is well known that these pressures typically correlate poorly with actual catheter-derived measurements [21].…”