Pathophysiology of the right ventricle and of the pulmonary circulation in pulmonary hypertension: an update

Abstract

The function of the right ventricle determines the fate of patients with pulmonary hypertension. Since right heart failure is the consequence of increased afterload, a full physiological description of the cardiopulmonary unit consisting of both the right ventricle and pulmonary vascular system is required to interpret clinical data correctly. Here, we provide such a description of the unit and its components, including the functional interactions between the right ventricle and its load. This physiological description is used to provide a framework for the interpretation of right heart catheterisation data as well as imaging data of the right ventricle obtained by echocardiography or magnetic resonance imaging. Finally, an update is provided on the latest insights in the pathobiology of right ventricular failure, including key pathways of molecular adaptation of the pressure overloaded right ventricle. Based on these outcomes, future directions for research are proposed.

Cardiac Catheterization versus Echocardiography for Monitoring Pulmonary Pressure: A Prospective Study in Patients with Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

“…Impaired right ventricular function is associated with mortality, and improvement of RV function might be a significant aim of treatment [21]. Therefore, in addition to the small size, a limitation of our study might be that we did not record other markers of RV dysfunction [22]. Further limitations are the lack of quality assessment of Doppler curve, by using a predefined score, as well as the noninvasive estimation of right atrial pressure from the combination of the inferior vena cava diameter and respiratory collapse [23].…”

Acute Respiratory Failure in Interstitial Lung Disease Complicated by Pulmonary Hypertension

“…Progressive PH may also result in hemodynamic collapse through prolonged RV contraction that continues beyond LV contraction, impairing LV filling [48]; disrupting systolic right coronary artery (RCA) perfusion and dependence on RCA diastolic perfusion of the RV [45,46,48,49]; and ventriculoarterial uncoupling [reduced end-systolic elastance of the RV(Ees)/pulmonary arterial elastance(Ea)] to promote RVF [43,50]. Uncoupling describes insufficient energy transfer from the ventricle to the arterial load, increasing the myocardial oxygen demand.…”

Novel non-pharmacological therapy to modulate the autonomic tone in patients with heart failure with pulmonary hypertension

“…In the study by Chen et al, pulmonary artery denervation (PADN) using catheter ablation improved hemodynamic function, exercise capacity and reduced PAH-related events and death in patients with PAH (mean PA pressure ≥25 mmHg at rest) of different causes (7). Given the fact that right HF in PAH is the consequence of increased arterial afterload, a full description of the cardiopulmonary unit is required (10). The cardiopulmonary unit is composed of two functional subsystems: the RV (contractility and chamber stiffness) and the pulmonary circulation (resistance and compliance).…”