For older male patients with heart failure and left ventricular hypertrophy, erectile dysfunction medications may protect the heart,  a meta-analysis published online Oct. 18 in BMC Medicine found. The researchers also reported that the drugs were safe and well tolerated.

Researchers from Rome reviewed 24 studies linking use of phosphodiesterase type 5 inhibitors (PDE5i) in cardiac patients. The meta-analysis included articles published between January 2004 and May 2014 with the intent to determine if PDE5i treatments were safe and effective for cardiac protection. The studies gave patients either oral sildenafil (Viagra, Pfizer), tadalafil (Cialis, GlaxoSmithKline), vardenafil (Levitra, Bayer Pharmaceuticals) or a placebo. Efficacy outcomes included changes in cardiac performance and geometry, neuroendocrine biomarkers and hemodynamic/endothelial parameters.

Elisa Giannetta, MD, PhD, of the experimental medicine department at Sapienza University of Rome, and colleagues found certain markers changed in different patient groups. For example, sildenafil appeared to reduce the left ventricular mass index for patients with left ventricular hypertrophy by 12.2 g/m². Meanwhile, nonhypertrophic patients had an increase of end-diastolic volume index by 4.99 mL/m².

Improvements to cardiac performance appeared across all patient categories. Cardiac index increased by 0.3 L/min/m² in patients given sildenafil and vardenafil over placebo. Specifically, patients without left ventricular hypertrophy increased cardiac index performance by 0.35 L/min/m². Cardiac index improvements were also seen in patients with left or right heart disease, by 0.29 L/min/m² and 0.3 L/min/m² respectively.

Ejection fraction improved in patients with left heart disease by 3.56 percent when given sildenafil over placebo; patients with left ventricular hypertrophy had greater improvement (4.38 percent) on sildenafil vs. placebo. Similar benefits were seen for patients with left ventricular hypertrophy to neuroendocrine biomarkers and endothelial function of patients who were older than 60.

Their meta-analysis showed that overall PDE5i therapy had a good safety profile with adverse event rates similar to placebo.

Giannetta et al found that in order for patients to see adequate benefit, however, they need long-term treatment and must have a certain amount of hypertrophy to begin with. “Our data show that only when the compensatory mechanisms evolve into changes in cardiac geometry do the benefits of PDE5i on EF [ejection fraction] become clinically detectable,” they wrote.

They did note, however that while effects on cardiac remodeling and function were seen, little data existed on how these drugs affected outcomes in women. In men, on the other hand, Giannetta et al wrote, PDE5i could be helpful in treating cardiac hypertrophy and early stage heart failure.