Impact of Underlying Pulmonary Arterial Hypertension on the In-Hospital Outcomes of Patients Admitted Due to Atrial Fibrillation, Atrial Flutter, Ventricular Tachycardia, or First Myocardial Infarction: A Nationwide Analysis (2016-2020).

Background Pulmonary Arterial Hypertension (PAH) is known to impact heart disease outcomes. In this analysis, we aim to analyze the impact of atrial fibrillation/atrial flutter (AF), ventricular tachycardia (VT), or a first myocardial infarction (MI) episode on patients with PAH. This will improve understanding of the clinical impact of underlying PAH in patients who develop these conditions to create a risk stratification process and possibly guidelines regarding their management. Methods In this National Inpatient Sample Database (2016-2020) analysis, patients admitted with a primary diagnosis of AF, VT or first MI episode, with or without a secondary diagnosis of PAH were identified using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes. The primary outcome was mortality. Secondary outcomes included the length of stay, resource utilization, and the necessity for endotracheal intubation and cardiac assistance devices. Univariate analysis included hospital-level and patient baseline characteristics such as age, gender, race, Charlson comorbidity index, hospital location, size, region, teaching status, and insurance. Baseline characteristics with p-value <0.2 were considered significant and adjusted in a multivariate analysis. Data was statistically significant if p-value <0.05. Results From 2016 to 2020, out of the adults admitted for AF (n=2,292,194), VT (n=241,225), and first MI (n=2,567,159), those who had PAH were 119,095, 12,470, and 79,895, respectively. Appropriate diagnosis and classification of PAH is essential for identifying the possible complications associated with this condition. Patients admitted for AF with a secondary diagnosis of PAH had a higher mortality risk (OR 1.22; 95% CI 1.09-1.37; p=0.001), longer length of stay in days (regression coefficient 0.89; 95% CI 0.82-0.96; p<0.001), greater resource utilization in dollars (regression coefficient 11510.71; 95% CI 10120.46-12900.97; p<0.001) and more endotracheal intubations (OR 1.69; 95% CI 1.46-1.96; p<0.001), but showed no difference on cardioversions (OR 1.10; 95% CI 0.94-1.29; p=0.241). Patients admitted due to VT with a secondary diagnosis of PAH also had a higher mortality risk (OR 1.39; 95% CI 1.13-1.71; p=0.002), greater length of stay in days (regression coefficient 1.22; 95% CI 0.87-1.58; p<0.001), higher resource utilization (regression coefficient 25332.61; 95% CI 16305.56-34359.66; p<0.001), and more endotracheal intubations (OR 1.37; 95% CI 1.11-1.68; p=0.003) and cardioversions (OR 1.13; 95% CI 1.25-1.36; p<0.001). Adjusted outcomes showed that patients with PAH admitted for first MI had an increased in-hospital mortality risk (OR 1.11; 95% CI 1.03-1.2; p=0.006), length of stay (regression coefficient 1.35; 95% CI 1.21-1.48; p<0.001), hospital charges (regression coefficient 23050.94; 95% CI 18952.86-27149.03; p<0.001), and rate of intubation (OR 1.24; 95% CI 1.14-1.35; p<0.001).  Conclusion Our investigation shows a clear detrimental trend in patients that are admitted to the hospital with AF, VT, and first MI along with an underlying history of PAH. Compared to those without a history of this pulmonary condition, such patients have an increased mortality rate as well as an increased length of hospital stay, higher hospital charges and some other in-hospital complications. More studies are necessary to assess the impact of specific therapies for PAH in order to evaluate the effect on outcomes.