Pulmonary Hypertension in Aortic and Mitral Valve Disease

Abstract

In patients with aortic and/or mitral valve disease the presence of pulmonary hypertension (PH) indicates a decompensated state of the disease with left ventricular and left atrial dysfunction and exhausted compensatory mechanism, i.e., a state of heart failure. Pulmonary hypertension in this context is the consequence of the backwards transmission of elevated left atrial pressure. In this form of PH, pulmonary vascular resistance is initially normal (isolated post-capillary PH). Depending on the extent and chronicity of left atrial pressure elevation additional pulmonary vascular remodeling may occur (combined pre- and post-capillary PH). Mechanical interventions for the correction of valve disease often but not always reduce pulmonary pressures. However, the reduction in pulmonary pressures is often modest, and persistent PH in these patients is common and a marker of poor prognosis. In the present review we discuss the pathophysiology and clinical impact of PH in patients with aortic and mitral valve disease, the comprehensive non-invasive and invasive diagnostic approach required to define treatment of PH, and recent insights from mechanistic studies, registries and randomized studies, and we provide an outlook regarding gaps in evidence, future clinical challenges, and research opportunities in this setting.

Keywords: aortic stenosis; combined pre- and post-capillary; mitral regurgitation; post-capillary; pre-capillary; pulmonary hypertension; valve disease.

Figure 1

Normal hemodynamic situation of the circulation from the right heart across the lung and the left heart. AV: aortic valve, CO₂: carbon dioxide, LA: left atrium, LAP: left atrial pressure, LV: left ventricle, LVEDP: left ventricular enddiastolic pressure, mPAP: mean pulmonary artery pressure, mPAWP: mean pulmonary artery wedge pressure, MV: mitral valve, PA: pulmonary artery, PV: pulmonary veins, PVR: pulmonary vascular resistance, O₂: oxygen, RV: right ventricle.

Figure 2

Hemodynamics of pulmonary hypertension (PH) other than group 2 PH in a patient with non-severe mitral stenosis (MS), mitral regurgitation (MR), aortic stenosis (AS), or aortic regurgitation (AR). PAH: pulmonary arterial hypertension, CTEPH: chronic thromboembolic PH. * typically relatively low. Other abbreviations as in Figure 1.

Figure 3

Hemodynamics of group 2 pulmonary hypertension due to non-valve disease related left ventricular (LV) dysfunction in a patient with non-severe mitral stenosis (MS), mitral regurgitation (MR), aortic stenosis (AS), or aortic regurgitation (AR). Other abbreviations as in Figure 1.

Figure 4

Suggested algorithm to detect pulmonary hypertension (PH) using echocardiography (echo) and right heart catheterization (RHC) in patients with left-sided valve disease (VD, i.e., mitral stenosis and/or regurgitation, aortic stenosis and/or regurgitation). ¹low probability of PH: peak TRV ≤2.8 m/s and no indirect echocardiographic signs of PH ²intermediate probability of PH: peak TRV ≤2.8 m/s but indirect signs of PH or if peak TRV but without indirect signs of PH, high probability of PH: peak TRV 2.9–3.4 m/s with indirect signs of PH or peak TRV ≥3.4 m/s regardless of indirect signs of PH ³please see Figure 3.

Figure 5

Hemodynamics of severe mitral stenosis (MS). It should be noted that the LV is not affected by the valvular problem, and LVEDP is normal. A significant diastolic gradient between LVEDP and PAWP is characteristic. Abbreviations as in Figure 1.

Figure 6

Hemodynamics of severe primary mitral regurgitation (MR). There is volume overload and dilatation of the both LV and LA. Abbreviations as in Figure 1.

Figure 7

Hemodynamics of severe aortic stenosis (AS). There is pressure overload of the LV with concentric hypertrophy. The LA is secondarily affected by diastolic and systolic LV dysfunction. Abbreviations as in Figure 1.

Figure 8

Hemodynamics of severe aortic regurgitation (AS). There is volume overload and dilatation of the LV. The LA is secondarily affected by diastolic and systolic LV dysfunction. Abbreviations as in Figure 1.