NEW YORK, May 5 (Reuters) Long-term cocaine use may be associated with regional left ventricular dysfunction, a condition that reduces the heart's pumping efficiency and increases the risk of heart failure, according to researchers at Johns Hopkins Medical Institutions in Baltimore.
''Since cocaine use is quite popular in this country,'' senior investigator Dr. Shenghan Lai told Reuters Health, ''physicians need to know cocaine use may cause left ventricular dysfunction.'' He notes that MRI imaging can be used to detect the earliest signs of functional impairment of the heart muscle in these patients.
Lai and colleagues used MRI to measure the heart's midwall circumferential strain (Ecc), a marker of regional left ventricular function, in 32 long-term cocaine users and 14 individuals who did not use cocaine. The findings are reported in the American Journal of Cardiology.
Overall left ventricular function did not differ significantly between the cocaine users and nonusers, the authors report. The only anatomic difference between the two groups was a larger average left ventricular mass in the cocaine users.
However, the average Ecc measurements during the diastolic phase (the bottom number of the blood pressure reading) of heart contraction were smaller in the cocaine users than in the nonusers for 15 of the 16 ventricular segments evaluated.
Similarly, the researchers note, the average Ecc measurements in the systolic phase (the top number of the blood pressure reading) were smaller in the cocaine users for 11 of the 16 ventricular segments. But none of these differences were statistically significant.
The Ecc disparities between the two groups did not appear to fit into any anatomic pattern, the report indicates.
Two previous studies have indicated a relationship between abnormal diastolic function of the heart and the long-term use of cocaine, the investigators point out. ''The present study is further proof for this association between long-term cocaine use and abnormal cardiac diastolic function, and it indicates that cocaine-related diastolic dysfunction develops regionally in the left ventricle.'' If left ventricular dysfunction is identified early, the right treatment might slow or reverse this serious heart condition, Lai added.
REUTERS CH ND0908