Myocardial Ischemia During Mental Stress: Role of Coronary Artery Disease Burden and Vasomotion

Abstract

BackgroundMental stress–induced myocardial ischemia (MSIMI) is associated with adverse prognosis in patients with coronary artery disease (CAD), yet the mechanisms underlying this phenomenon remain unclear. We hypothesized that compared with exercise/pharmacological stress–induced myocardial ischemia (PSIMI) that is secondary to the atherosclerotic burden of CAD, MSIMI is primarily due to vasomotor changes.Methods and ResultsPatients with angiographically documented CAD underwent 99mTc‐sestamibi myocardial perfusion imaging at rest and following both mental and physical stress testing, performed on separate days. The severity and extent of CAD were quantified using the Gensini and Sullivan scores. Peripheral arterial tonometry (Itamar Inc) was used to assess the digital microvascular tone during mental stress as a ratio of pulse wave amplitude during speech compared with baseline. Measurements were made in a discovery sample (n=225) and verified in a replication sample (n=159). In the pooled (n=384) sample, CAD severity and extent scores were not significantly different between those with and without MSIMI, whereas they were greater in those with compared with those without PSIMI (P<0.04 for all). The peripheral arterial tonometry ratio was lower in those with compared with those without MSIMI (0.55±0.36 versus 0.76±0.52, P=0.009). In a multivariable analysis, the peripheral arterial tonometry ratio was the only independent predictor of MSIMI (P=0.009), whereas angiographic severity and extent of CAD independently predicted PSIMI.ConclusionsThe degree of digital microvascular constriction, and not the angiographic burden of CAD, is associated with MSIMI. Varying causes of MSIMI compared with PSIMI may require different therapeutic interventions that require further study.

Association Between Anger and Mental Stress-Induced Myocardial Ischemia

“…However, mental stressinduced myocardial ischemia is known to be unrelated to severity of coronary obstruction or previous revascularization, and can occur in the setting of a negative exercise-or adenosinestress test. 3 We are unable to explain why mental stress-induced myocardial ischemia shows a robust relationship only with state/trait anger, and not with anger expression, but our results are consistent with a recent meta-analysis, 6 where an association with CHD was found for trait anger but not for anger-expression. Another limitation is the lack of CHD outcome data.…”

“…2 Mental stress ischemia is analogous to exercise or pharmacologically-induced myocardial ischemia during standard cardiac testing (here referred together as "physical stress-induced myocardial ischemia"), except that the stressor used is psychological instead of physical. 2 Mental stress ischemia has similar prognostic value to physical stress ischemia, but is typically painless, occurs at lower levels of oxygen demand, and is not related to severity of coronary artery disease (CAD) 2,3 , or previous revascularization. 2,3 Mental stress, but not physical stress-induced myocardial ischemia, correlates with myocardial ischemia measured in daily life ambulatory monitoring 4 and is associated with worse prognosis in subjects with stable CHD, with a twofold increased risk of future cardiac events independent of physical stress-induced ischemia.…”

“…2 Mental stress ischemia has similar prognostic value to physical stress ischemia, but is typically painless, occurs at lower levels of oxygen demand, and is not related to severity of coronary artery disease (CAD) 2,3 , or previous revascularization. 2,3 Mental stress, but not physical stress-induced myocardial ischemia, correlates with myocardial ischemia measured in daily life ambulatory monitoring 4 and is associated with worse prognosis in subjects with stable CHD, with a twofold increased risk of future cardiac events independent of physical stress-induced ischemia. 5 Anger has long been considered a potential precipitant of acute myocardial infarction (MI) and a significant risk factor for CHD.…”

Mental stress-induced myocardial ischaemia

“…Earlier studies suggested an association between fall in global LVEF and extent of CAD 40. More recently, however, the degree of MSIMI was reported to be independent of the extent or severity of CAD,45 in contrast to exercise-induced ischaemia. Reductions in global LVEF, without convincing evidence of coincident perfusion deficits or regional wall motion abnormalities,46 have also been observed in individuals without significant CAD, implying that alternative mechanisms may also exist for cardiac dysfunction during mental stress.…”

The interface of emotion and biology in myocardial ischemia: Can we progress using the traditional paradigm?

“…In addition, MSIMI has been observed in a substantial percent of patients who do not demonstrate myocardial ischemia during exercise or pharmacologic stress. 26 Thus, while the findings of Haaf et al-even with the small event rate-may be seen as a wakeup call, the approach taken in the research methods with the reliance on exercise and pharmacologic stress may be just the tip of the iceberg insofar as what might be expected as a higher event rate if mental stress testing was also included.…”