PAH Heightens Mortality Risk, Cost for People with Cardiac Diseases

People admitted to the hospital for atrial fibrillation (AF), first myocardial infarction (MI), and other cardiac conditions have a higher risk of death and a longer average hospital stay if they also have a history of pulmonary arterial hypertension (PAH), a new report has found.

The findings show how PAH can add significant cost and complications to inpatient hospital care.

PAH has become the subject of increasing attention in recent years due to its debilitating effects and the lack of an effective cure. As a result, many efforts have focused on ways to develop better therapies and better ways to more quickly diagnose the disease.

One problem, according to Christian Siochi, M.D., of the Montefiore New Rochelle Hospital, and colleagues, is that comorbidities such as arrhythmias and ischemic heart disease can mask symptoms of PAH, making it harder to correctly and efficiently diagnose it.

They noted that atrial arrhythmias in patients with PAH are marked by the enlargement of the right atrium and the presence of right-heart failure, making patients predisposed to AF.

“On the other hand, a low incidence of ventricular arrhythmias, such as ventricular tachycardia (VT) and ventricular fibrillation, has been noted in patients with PAH compared with those with primarily left ventricular failure,” they noted in a new study published in the journal Cureus. They added that research indicates supraventricular arrhythmias are associated with clinical deterioration in PAH, leading to higher rates of hospitalization and other high-cost care.

PAH is also thought to increase the risk of MI due to the mechanical pressure caused by high pulmonary venous pressure.

Siochi and colleagues wanted to better understand the ways in which PAH adds to the burden experienced by people hospitalized for arrhythmias and myocardial infarction. To find out, they used the National Inpatient Sample database (2016-2020) to identify patients who were admitted to the hospital with a primary diagnosis of atrial fibrillation, ventricular tachycardia or first myocardial infarction. They found approximately 2.3 million atrial fibrillation admissions, 241,000 ventricular tachycardia admissions, and 2.6 million first myocardial infarction admissions. Of those patients, 119,095 patients admitted for atrial fibrillation also had PAH, 12,470 patients with ventricular tachycardia also had PAH, and 79,895 first myocardial infarction patients had PAH.

The impact of PAH was significant. In terms of mortality, patients with PAH had an elevated risk of death if they had atrial fibrillation, ventricular tachycardia or first myocardial infarction compared with those without PAH. Patients with any of the comorbidities also had longer hospital stays than their non-PAH peers, and they had higher resource utilization and/or hospital charges, Siochi and colleagues found.

“This analysis revealed that PAH has a negative impact on the outcomes of patients admitted with certain cardiovascular events,” they said. “Further studies are needed to elucidate the need for specific treatments based on the severity of the underlying disease.”

The investigators said their study had certain limitations associated with the database they used. While the National Inpatient Survey is the largest database of hospital-stay information, it does not include details commonly found in electronic health records, such as PAH severity and a list of medications administered. Those limitations also meant the investigators could not account for the possible influence of PAH therapies. Furthermore, the database does not include patients’ primary causes of death, which is why the study used all-cause mortality.

Nonetheless, Siochi and colleagues said the data suggest PAH is associated with inferior outcomes among people with common cardiac complications. Better awareness of this fact, they said, could lead to better outcomes for patients with PAH.