Cardiac abnormalities and HIV

HIV itself may increase the risk of heart disease. Cardiac abnormalities (including reduced heart muscle mass and reduced ability of the heart to relax between contractions allowing blood to flow into the heart) have been observed among people with HIV and may foreshadow later heart failure. Studies have also linked HIV infection and higher viral loads to impaired endothelial function, the ability of the blood vessels to dilate in response to increased blood flow - the earliest detectable sign of future cardiovascular disease.¹

Despite antiretroviral treatment, markers of inflammation usually related to chronic viral infection and implicated in the long-term development of heart disease are likely to be higher in people with HIV than in healthy adults of the same age, according to recent study results.²

When researchers compared HIV-infected individuals who had well-controlled viral load and at least six months of antiretroviral treatment (ART) to matched HIV-negative counterparts, the HIV-positive participants had significantly higher levels of all inflammation markers, apart from soluble tumour necrosis factor receptor 1 and 2, and higher levels of the activation marker sVCAM-1. They also had greater intima media thickness in two separate measures. The inflammatory markers that positively correlated with internal intima media thickness were sVCAM-1, myeloperoxidase, and TNF-alpha. 

Another study performed a baseline evaluation in ART-naive patients to assess cardiovascular risk using traditional risk factors, immunologic data, Framingham risk score (FRS), and detection of subclinical carotid lesions using colour Doppler ultrasound.³

The presence of carotid lesions was significantly related to sedentary lifestyle, age, the FRS, advanced HIV stage, and viral load above 100,000 copies/ml. These results indicate that HIV infection itself is a risk factor for atherosclerosis and recommend ultrasound assessment for patients with advanced HIV disease and an FRS of six percent or more.  

Children and infants who are infected with HIV from birth have worse cardiac function than other children.⁴ A five-year study of approximately 300 HIV-infected infants and young children has found 18-39% developed heart dysfunction that was associated with an increased risk of death.⁵ The mechanisms that lead to cardiac abnormalities among adults and children with HIV have not been established but malnourishment is one factor associated with abnormalities.⁶

There have been reports linking the use of antiretroviral drugs during pregnancy to heart problems in infants. However, the balance of current evidence indicates that NRTIs do not cause neurologic or cardiac problems in infants exposed in the womb.⁷ One recent prospective study of over 600 infants found zidovudine had no impact on the left ventricular structure or heart function of infants as assessed during 14 months of follow-up. AZT exposure also did not affect fractional shortening at 10-14 months while the impact on left ventricular mass was inconsistent. ⁸