Patients With Obesity Exhibit a Plateau Pattern of the Right Ventricular Waveform

BACKGROUND: Ventricular waveforms are characterized by a dip-and-plateau pattern during diastole owing to an abrupt termination of ventricular filling because of pericardial constraint under conditions such as constrictive pericarditis (CP). However, constrictive hemodynamics is not specifically caused by CP. Therefore, this study aimed to evaluate whether patients with obesity exhibited constrictive hemodynamics. METHODS: Overall, 60 consecutive Japanese patients (mean age, 69.5 years; 45% women) who underwent right heart catheterization at the Japan Community Healthcare Organization Osaka Hospital from July 2016 to September 2018 were examined. Two-dimensional echocardiography was used to measure the epicardial adipose tissue (EAT) in the standard parasternal long-axis view during end-diastole. Because patients who underwent open-heart surgery were highly likely to have CP, they were excluded. RESULTS: Among the 60 patients, 11 (18%) exhibited a plateau pattern of the right ventricular waveform and had a mean EAT value of 4.2 mm, which was significantly higher than that of patients without such a pattern (2.1 mm, P < 0.001). Similarly, the mean body mass index (BMI) values were significantly higher in patients with a plateau pattern than in those without it (27.2 vs. 21.8 kg/m(2), P < 0.001). EAT was significantly correlated with the BMI (r = 0.72, P < 0.001). In patients with a plateau pattern, the triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) levels were significantly higher (TG: 150 vs. 100 mg/dL, LDL-C: 121 vs. 95 mg/dL, P < 0.05) and the left atrial diameter (52.8 vs. 44.7 mm, P < 0.01) and left atrial volume index (58.7 vs. 47.6 mL/m(2), P < 0.05) were significantly greater than those in the patients without it. The EAT was also significantly correlated with the TG level (r = 0.37, P < 0.01). CONCLUSIONS: Obese patients may present with constrictive hemodynamics, suggesting left ventricular diastolic dysfunction. EAT was significantly correlated with metabolic syndrome components, namely obesity and TG levels.