Pulmonary Hypertension Due to Left Ventricular Cardiomyopathy: Is it the Result or Cause of Disease Progression?

Abstract

Purpose of review: The purpose of this review is to define pulmonary hypertension in the setting of left heart disease (PH-LHD), discuss its epidemiology and pathophysiology, and highlight the cause and effect relationship it has with disease progression in the setting of cardiomyopathy.

Recent findings: Both pulmonary hypertension (PH) and heart failure are becoming increasingly common. As such, PH-LHD is now the most common form of PH. The pathophysiology of the condition relates to backward transmission of elevated left ventricular filling pressures into the pulmonary circulation and, ultimately, right ventricular (RV) strain/dysfunction. It is evident that these pathophysiologic processes are both the effect and cause of left heart disease progression. In this review, we describe the complex relationship between disease progression in left ventricular cardiomyopathy and PH-LHD. Clinicians and researchers should take note of the importance of PH-LHD and RV dysfunction to appropriately risk stratify patients and develop therapies for the condition.

Keywords: Cardiomyopathy; Heart failure; Left heart disease; Pulmonary hypertension; Valvular heart disease; WHO group 2.

Fig. 1

Cardiopulmonary interaction and pathobiology of pulmonary hypertension (PH) in left ventricular heart failure. Shown is (i) the backward transmission of elevated left ventricular filling pressures into the pulmonary circulation (post-capillary hemodynamic profile), (ii) potential superimposed components contributing to the extent of PH (leading to a pre-capillary component), which may be associated with (iii) pulmonary vascular remodeling in some patients, thus leading to (iv) right ventricular strain and dysfunction over time. Right ventricular (RV) dilation and increase in wall stress/tension (internal RV afterload) result in elevated myocardial oxygen consumption, which with concomitant reduction in coronary perfusion gradient leads to RV ischemia and progressive RV failure [6]

Fig. 2

Echocardiographic manifestations of Cpc-PH. a reveals a pulmonary valve acceleration time (AT) as well as a right ventricular outflow tract pulse-wave spectral Doppler notch (arrow). b reveals systolic interventricular septal flattening (double arrows). Finally, c illustrates a low tricuspid annular systolic plane excursion (double-headed arrow) which is indicative of decreased right ventricular function. All three of these features are consistent with the presence of Cpc-PH rather than Ipc-PH