Heart Failure Patients With HIV Face Higher Risk of Sudden Cardiac Death

By Will Boggs MD

August 21, 2019

NEW YORK (Reuters Health) - The risk of sudden cardiac death (SCD) appears to be higher among heart failure patients who also have HIV infection, according to new findings.

"Data from San Francisco among patients with HIV and without heart failure showed that persons with HIV were at an elevated risk of sudden death," Dr. Tomas G. Neilan from Massachusetts General Hospital in Boston told Reuters Health by email. "What is unique is that we have now shown this in persons with HIV who also have heart failure."

Dr. Neilan and colleagues used data from a prospective observational registry at Bronx-Lebanon Hospital Center of Icahn School of Medicine at Mount Sinai, in New York City, to analyze the incidence of SCD among people living with HIV (PHIV) hospitalized with heart failure and the risk factors associated with it.

They defined SCD, the primary outcome, as death within one hour of onset of symptoms if witnessed or within 24 hours of being observed alive and asymptomatic if unwitnessed or unexpected out-of-hospital death.

The study included 2,149 individuals hospitalized with heart failure without an implantable cardioverter defibrillator (ICD), including 344 PHIV. Compared with other patients, PHIV were more likely to have coronary-artery disease, elevated pulmonary-artery systolic pressure, cocaine use and co-infection with hepatitis C virus.

During a median follow-up of 19 months, there were 191 SCDs, with a significantly higher rate among PHIV (21%) than among non-HIV-infected individuals (6.4%), the researchers report in JACC: Heart Failure, online August 5.

In a multivariable model, factors independently associated with SCD among PHIV included coronary-artery disease, lower CD4 count or non-suppressed viral load, cocaine use, non-prescription of beta-blockers, low left ventricular ejection fraction (LVEF), wider QRS and increased corrected QT duration.

In stratified analyses, the SCD rate was significantly higher among PHIV than among non-HIV-infected patients with preserved LVEF (50% or higher), borderline LVEF (35-49%), or reduced LVEF (below 35%).

The SCD rate was also significantly higher among women with HIV than among HIV-uninfected women and higher among African Americans living with HIV than among non-African Americans living with HIV.

Physicians should "recognize this as a higher-risk group and consider HIV status when discussing standard measures to prevent sudden death, such as placement of a defibrillator," Dr. Neilan said. "Decades ago, there was a hesitation to place ICDs in this group. In contemporary cohorts with HIV and on antiretroviral therapy, HIV status should act as a reason to place an indicated ICD and not as a reason not to place one."

"Recognize that there are risk factors for sudden death which are unique to this group," he said. "Specifically, that lower viral load was associated with a reduced risk for sudden cardiac death."

"Individuals with HIV are aging and are facing a 2-fold heightened risk for heart failure," Dr. Neilan added. "Once individuals with HIV develop heart failure, their cardiac outcomes (sudden death and heart failure hospitalizations) are worse. We need to better understand why and come up with plausible ways of both reducing the risk for heart failure and improving outcomes in this at-risk population. We are performing additional studies to better understand the pathophysiology behind the heightened risk of sudden death in HIV."

In a linked editorial, Dr. Zian H. Tseng of the University of California, San Francisco, cautions, "Without postmortem data, SCDs adjudicated retrospectively by WHO criteria should be considered 'presumed' SCDs."

"In our recent POST SCD study (POstmortem Systematic Investigation of Sudden Cardiac Death), we collaborated with the medical examiner to prospectively identify and autopsy all 525 incident, WHO-defined SCDs (HIV and non-HIV) occurring countywide over a 3-year period," he explains. "We found that only half (55.8%) were actually arrhythmic after excluding non-cardiac (e.g., pulmonary embolism, acute hemorrhage, occult overdose, infection) and non-arrhythmic (e.g., tamponade, acute heart/pump failure) causes. In other words, WHO criteria had only a 56% positive predictive value for true arrhythmic death - essentially a coin-flip for SCD."

"Therefore, unintentional misclassification of approximately half of WHO-defined SCDs as cardiac is a critical limitation of the current study, our prior HIV SCD study, and indeed nearly all studies of SCD, HIV and non-HIV," Dr. Tseng notes.

"Before we conclude that PHIV and heart failure (HF) may only need close surveillance for lethal arrhythmia, and certainly before we leap to proposing different ICD, LifeVest, or subcutaneous ICD thresholds for PHIV with HF, the relative contributions of true arrhythmic vs. nonarrhythmic causes of sudden death are needed," he concluded. "Absent these data, we should interpret the current study to mean that PHIV and HF are at high risk of sudden mortality overall, and that providers should focus on measures to reduce the risk of all causes - arrhythmic, HIV-related, HF, and illicit drug use."

SOURCE: https://bit.ly/31TuwjE and https://bit.ly/2NkOhMY

JACC Heart Fail 2019.