PH After Heart Attack Linked to High Risk of Heart Failure in Study
Among people who have had a heart attack, those with pulmonary hypertension (PH) are at high risk of heart failure, according to a new study.
The study, “Clinical impact of pulmonary hypertension on the outcomes of acute myocardial infarction patients with or without chronic obstructive pulmonary disease,” was published in the journal Medicine.
A heart attack — also called acute myocardial infarction, or AMI — occurs when blood flow to the heart is blocked, which starves the heart muscle of oxygen and results in heart tissue death. Damage to the heart from AMI can help to set the stage for pulmonary hypertension, or high blood pressure in the lungs.
Scientists reported data for 318 people who’d been treated for heart attack at Chonnam National University Hospital, in Korea, from November 2011 to December 2015. Among these patients, 109 had chronic obstructive pulmonary disease (COPD), an inflammatory disease that affects the lungs.
Measures of pulmonary blood pressure suggested that 52 patients in the COPD group, as well as 100 participants without COPD — just under half of the 209 patients in this group — had PH following the heart attack, as assessed by a right ventricular systolic pressure of at least 35 mmHg. This measure is used to estimate the pressure inside the artery that supplies the lung with blood.
Here, the scientists compared outcomes among the patients with or without PH. In particular, the team looked for added risks during reperfusion therapy, or treatment following a heart attack to restore blood flow in blocked arteries.
“We hypothesized that PH may increase complications during hospitalization for reperfusion therapy for AMI and affect clinical outcomes in these patients,” the team wrote.
Overall, a greater proportion of patients with PH than without experienced new-onset heart failure: 25% versus 10.5% in the COPD group, and 19% versus 4.6% in the non-COPD group. Of note, heart failure is a chronic condition that develops when the heart cannot adequately pump blood out to meet all of the body’s needs.
Unadjusted statistical analyses indicated that PH was associated with a higher risk of heart failure, but adjusted analyses — which took into account other factors, like how PH patients without COPD were older and had a higher proportion of women — found no difference in heart failure risk based on PH status.
Similarly, with a follow-up time of about a year, more patients with PH than without died of any cause, but adjusted statistical analyses found no difference in mortality risk according to PH status.
“The PH group had high rates of new-onset HF [heart failure] regardless of the presence or absence of COPD … the incidence rates of all-cause mortality were higher in the PH group than in the no PH group,” the researchers wrote.
“Although these 1-year clinical outcomes were merely the analytic results of unadjusted data and were statistically attenuated in [adjusted] analysis, these trends were worthy of note,” they added.
Among participants with COPD, more people with PH than without (15.4% vs. 1.8%) experienced cardiogenic shock, a condition in which the heart suddenly cannot pump out enough blood to the body. Notably, PH was associated with an increased risk of cardiogenic shock even in adjusted analyses.
The researchers noted that this was a small study done at a single center, stressing a need for further research.