Indians have an increased risk for coronary artery disease (heart disease) not because the diameters of their arteries are relatively smaller but because of their smaller body surface area, a study conducted by researchers from the Department of Cardiology and Radiology at Sir Ganga Ram Hospital has found. The result of a test that 250 patients were subjected to has been published in the Journal of Indian College of Cardiology.

Another credible study, “Coronary artery dimensions in normal Indians,” conducted by researchers Barendra Kumar Raut, Vijaysinh Namdeo Patil and George Cherian, the result of which was published in the Indian Heart Journal in 2017, had found already that while the indexed size of coronary arteries in Indian males and females was the same, the traditional belief of Indians having smaller coronary arteries was not entirely true.

“We found that coronary artery size when indexed to BSA was not statistically different in Indians as compared to Caucasians. It is also independent of gender. Indians have small size coronary arteries because of their smaller body surface area. This has great relevance to the performance and results of interventional procedures like angioplasty and coronary artery bypass graft surgery,” the researchers said in the 2017 paper.

The result of the recent study once again challenges the popular myth that Indians suffer more from heart disease due to the diameters of their arteries that are on average smaller than those of healthier communities. “We found that 51% were hypertensive, 18% were diabetic, 4% were smokers, 28% were dyslipidemic and 26% had a family history of heart disease,” Dr JPS Sawhney, Chairman, Department of Cardiology, Sir Ganga Ram Hospital and lead author of the paper said.

The author and senior consultant in the Department of Cardiology, Sir Ganga Ram Hospital, Dr Ashwani Mehta, explains: “The study found that the mean vessel diameters for males were significantly larger than those for females, but when indexed to body surface area, these values are not significant. There had been an assumption that Asians and particularly Indians have an increased risk for atherosclerosis (fatty deposit in arteries) because of their small coronary artery diameters.”

But the observation by experts suggests that the coronary artery dimensions in the Indian population are not small. But we do have smaller body surface areas. The reasoning that smaller dimensions of arteries are a risk factor for heart disease does not apply to the Indian population.

“This study was done to estimate the size of normal coronary arteries in the Indian population, index it to BSA, and see if there is any significant difference when compared to the caucasian population. This study also might provide some insight into the use of diameters indexed to BSA as a cutoff for deciding the need for revascularisation (a procedure that can restore blood flow in blocked arteries or veins),” Dr Bhuvnesh Kandpal, another author of the paper, said.