Objective: To ascertain whether pulmonary hypertension, as assessed noninvasively by continuous-wave Doppler of tricuspid regurgitation, can be an important independent factor in the prognosis of patients with ischemic or idiopathic dilated cardiomyopathy.
Design: Cohort study of consecutive patients with dilated cardiomyopathy in whom follow-up was obtained on all survivors for 28 months.
Setting: Outpatient cardiology private practice office in a tertiary care center.
Patients: Consecutive sample of 108 patients who presented for a scheduled office visit during a 15-month period.
Measurements: M-mode, two-dimensional, and Doppler echocardiographic examinations were done on all patients at entry into the study and on survivors 1 year later. All examinations included extensive pulsed- and continuous-wave Doppler evaluation for tricuspid regurgitation.
Main outcome measures: Overall mortality, mortality due to myocardial failure, and hospitalization for congestive heart failure.
Results: Twenty-eight patients had a high velocity of tricuspid regurgitation (greater than 2.5 m/s), and 80 patients had a low velocity (less than or equal to 2.5 m/s). After 28 months of follow-up, the mortality rate was 57% in patients with a high velocity compared with 17% in patients with a low velocity (difference of 40%, 95% CI, 20% to 60%). Hospitalization for congestive heart failure occurred in 75% and 26% of patients, respectively (difference of 49%, CI, 30% to 68%). Eighty-nine percent of patients with a high velocity either died or were hospitalized compared with only 32% of patients with a low velocity (difference of 57%, CI, 42% to 72%). The peak velocity of tricuspid regurgitation was the only prognostic variable selected using stepwise logistic regression models for the three outcome events.
Conclusion: Noninvasive assessment of pulmonary hypertension using continuous-wave Doppler of tricuspid regurgitation can predict morbidity and mortality in patients with ischemic or idiopathic dilated cardiomyopathy.