Patients with chronic kidney disease (CKD) often have cardiac disturbances and various cardiovascular conditions.

One possible explanation for this association might be coronary microvascular dysfunction, a type of coronary artery disease where the small blood vessels feeding the heart muscle do not work as they should.

This dysfunction is dangerous, since it increases risk of heart attack and heart failure.

Studying CKD and Heart Disease

A group of researchers from Harvard Medical School, the University of Alabama at Birmingham, and New York University School of Medicine investigated a possible link between chronic kidney disease, coronary microvascular dysfunction, and other cardiac disorders.

• 352 patients were examined by echocardiogram, positron emission tomography, and kidney function assessment.
• Estimated glomerular filtration rate, or eGFR, was measured to explore kidney function. (eGFR is an estimate of how much liquid and waste is passing from the blood through the small filters in the kidney, called glomeruli.)
• The researchers also measured coronary flow reserve, or CFR. (CFR shows the maximum increase in blood flow through the coronary arteries above normal resting volume. CFR data demonstrate the conditions of the coronary arteries.)

Disease Link

• The study showed that coronary microvascular dysfunction and CFR were linked to abnormal heart function and an increased risk of adverse cardiovascular events.
• The connection between impaired kidney function, heart dysfunction, and cardiovascular disease events was partially brought about by coronary microvascular dysfunction.
• Any relationship between eGFR and cardiac dysfunction was not found, however.

Concluded the authors, “Coronary microvascular dysfunction, but not eGFR, was independently associated with abnormal cardiac mechanics and an increased risk of cardiovascular events. Coronary microvascular dysfunction may mediate the effect of chronic kidney disease on abnormal cardiac function and cardiovascular events in those without overt coronary artery disease.”

Read the article in  Circulation.

*Bajaj, N.S.; Singh, A.; Zhou, W.; et al. (2020). Coronary Microvascular Dysfunction, Left Ventricular Remodeling, and Clinical Outcomes in Patients With Chronic Kidney Impairment. Circulation. 141(1), 21-33. [Epub].