Objective:
Patients with heart failure (HF) and pulmonary hypertension (PH) have worse outcomes after cardiac resynchronization therapy (CRT). The relationship of circulating HF biomarkers and right ventricular systolic pressure (RVSP) may provide insight to the mechanism between PH and poor CRT response.
Methods:
In 90 patients (age 65 ± 13, 78% male, EF 26 ± 8%, RVSP 44 ± 12 mmHg) undergoing CRT, we measured baseline RVSP by echocardiography and obtained peripheral blood samples drawn at the time of device implantation. We measured levels of established and emerging HF biomarkers (Table 1). CRT non-response was defined as no improvement of adjudicated HF Clinical Composite Score at 6 months. Major adverse cardiac event (MACE) was defined as composite endpoint of death, cardiac transplant, left ventricular assist device, and HF hospitalization within 2 years.
Results:
There were 34% CRT non-responders and 27% had MACE. Per 1 unit increase in log-transformed RVSP, there was an 11-fold increase risk of having CRT non-response (odd ratio [OR] 11.0, p=0.01) and over 5-fold increase of developing 2-year MACE (hazard ratio [HR] 5.8, p=0.02). When comparing patients with severe PH (RVSP>60 mmHg) to those without PH (RVSP < 35 mmHg), there was an 8-fold increase in CRT nonresponse (OR 8.4, p=0.03) but no difference in MACE (p=NS). RVSP was correlated with increased biomarker levels of myocardial stretch and fibrosis, but not myocardial necrosis (Table 1).
Conclusions:
Higher RVSP is associated with greater rates of CRT non-response and adverse clinical outcomes. The mechanistic association between severe PH and CRT nonresponse may be explained by the biomarker profile reflective of myocardial wall stretch and fibrosis.
Mitral valve lesion associated with secundum atrial septal defect. Analysis by real time two dimensional echocardiography.
