In coronary artery disease patients, too low blood pressure linked to worse outcomes: Study

In coronary artery disease patients, too low blood pressure is linked with worsened outcomes. Principal investigator Prof. Philippe Gabriel Steg explained, “The optimal blood pressure target in patients with hypertension continues to be debated, especially in those with coronary artery disease (CAD). ESC [European Society of Cardiology] guidelines recommend lowering blood pressure to values within the range 130-139/80-85 mm Hg for patients with CAD to reduce the risk of further cardiovascular events. Some argue ‘the lower, the better’ but there is a concern that patients with CAD may have insufficient blood flow to the heart if their blood pressure is too low.”

The study involved 22,672 patients with coronary artery disease enrolled in the CLARIFY registry and treated for high blood pressure (hypertension).

The researchers found that after five years, systolic blood pressure of 140 mm Hg or greater and diastolic blood pressure of 80 mm Hg or higher was associated with a greater risk of cardiovascular events.

Prof. Steg added, “These results were expected, and are in line with ESC recommendations to reduce blood pressure below these levels in patients with CAD.”

Systolic blood pressure below 120 mm Hg was also associated with some cardiovascular events, too. Diastolic blood pressure below 70 mm Hg also increased the risk of cardiovascular events.

Prof. Steg continued, “We found that systolic blood pressure less than 120 mm Hg was associated with a 56 percent greater risk of the composite primary outcome of cardiovascular death, myocardial infarction, or stroke. Diastolic blood pressure between 60 and 69 mm Hg was associated with a 41 percent increased risk of the primary outcome, with risk rising to two-fold when diastolic blood pressure fell below 60 mm Hg. This large study of hypertensive CAD patients from routine clinical practice found that systolic BP [blood pressure] less than 120 mm Hg and diastolic BP less than 70 mm Hg are each associated with adverse cardiovascular outcomes, including mortality. The findings support the existence of a J-curve phenomenon, where the initial lowering of BP is beneficial, but further lowering is harmful.”

Prof. Steg concluded, “Our results suggest that the ESC recommendation remains valid and physicians should exercise caution when using BP-lowering treatment in patients with CAD. This should however not detract from our efforts to diagnose and treat hypertension, which remains massively underdiagnosed and undertreated worldwide.”

Diagnosis and treatment options for coronary heart disease

Coronary heart disease (CHD) is incurable, but can be managed. Treatment for CHD involves lifestyle changes and medical interventions. Lifestyle recommendations include quitting smoking, eating a healthy diet, exercising regularly, managing diabetes, blood pressure, and cholesterol, reducing stress, and reducing your intake of sugar.

Medications can also benefit a person with CHD, including the use of statins to reduce cholesterol, aspirin to reduce blood clotting, and beta blockers for blood pressure regulation.

In some cases, surgery is required to treat CHD to open or replace blocked arteries.

With regards to diagnosing CHD, there are numerous tests your doctor can utilize including an electrocardiogram, a stress test, CT scans, blood tests, coronary catheterization, and nuclear ventriculography.