BACKGROUND - Pulmonary venous hypertension (PVH) is a well-described cause of pulmonary hypertension (PH) in patients with left heart disease associated with elevated left heart filling pressure. PVH results from a number of processes, including left-sided valvular disease, constrictive pericardial disease, restrictive cardiomyopathies, and left ventricular (LV) systolic dysfunction. PVH in patients with normal LV systolic function, commonly referred to as diastolic dysfunction, is not well characterized. We observed that many patients with PH due to PVH have obesity, hypertension, diabetes mellitus, and hypercholesterolemia, which are clinical features of the metabolic syndrome (MS), a previously identified cause for systemic vascular disease.
METHODS - We evaluated 122 consecutive patients referred for diagnosis and treatment of PH and compared the prevalence of features of the MS between patients with PVH and those with pulmonary arterial hypertension (PAH). We also compared clinical and hemodynamic characteristics between these two groups.
RESULTS - Compared to patients with PAH, patients with PVH had a higher frequency of hypertension, obesity, diabetes mellitus, and hyperlipidemia. Two or more features of the MS were found in 16 of 17 patients with PVH (94.1%) compared with 34.3% of patients with PAH (p < 0.001; odds ratio, 30.7; 95% confidence interval, 3.6 to 260.0). PH was substantial, but less severe overall, in patients with PVH compared to those with PAH (mean pulmonary artery pressure, 45 +/- 17 mm Hg [range, 26 to 71 mm Hg] vs 53 +/- 10 [range, 33 to 72 mm Hg], respectively [p = 0.041]; and pulmonary vascular resistance, 4.4 +/- 2.9 units [range, 1.2 to 10.8 units] vs 10.8 +/- 4.7 units [range, 4.8 to 21.9 units], respectively [p < 0.001]).
CONCLUSION - PVH is highly associated with the MS. Our results suggest that the MS may predispose patients to develop pulmonary vascular disease.