Exercise electrocardiography combined with stress echocardiography for predicting myocardial ischemia in adults

Results of bicycle exercise stress test in patients with stable coronary heart disease depending on the angiographic signs of atherosclerotic lesions of coronary arteries

The aim. To identify features of exercise response in coronary heart disease (CHD) patients depending on coronary artery condition and to identify factors associated with a positive test in patients with no obstructive coronary artery disease (INOCA). Materials and methods. The study included 105 patients diagnosed with stable coronary artery disease (CAD) who were hospitalized at the City Clinical Hospital No. 8 of the Kharkiv City Council. The criteria for diagnosis of ischemia with no obstructive coronary artery disease (INOCA) were met by 53 patients who formed group I. Group II included 52 patients who were consistently hospitalized in the period from June to December 2020, and had obstructive CAD for more than 50 % according to their coronary angiography (CAG). Results. According to the results of bicycle exercise stress test, a positive test was significantly more often registered in group II – n=30 (57.7 %) patients compared to group I – n=19 (35.8 %) patients (p=0.0249). The duration of the test in patients of group I was significantly longer than 420 seconds [290–540], compared with group II – 300.0 [210.0–540.0] (р=0.0352). Also, in patients in group II, the maximum volume of the test performed was probably lower than in group I (p=0.0324). When calculating the double product, it was also found that in group I its value was significantly higher compared to group II (p=0.0292). In group I there was a significantly higher rate of chronotropic reserve (44.0 [26.0–60.0]), compared with group II (p=0.0168). Elevated total cholesterol (above 5 mmol/l) is a statistically significant and independent factor of a positive exercise test in patients with INOCA (OR, 1.98 [0.9992-3.926], p=0.05). A correlation was found between the level of exercise tolerance and smoking in INOCA-patients (r =-0.388975, p=0.010899). Patients who underwent MINOCA also showed reduced tolerance to exercise (r=-0.3104, p=0.042721) Conclusions. The sensitivity of bicycle exercise stress test in patients with CAD depends on the presence and severity of atherosclerotic lesions of the coronary arteries (63 % in stenotic atherosclerosis, 36 % in no obstructive coronary arteries. It was found that exercise test duration, double product, chronotropic and inotropic reserve of the heart in patients with a positive exercise test with INOCA were significantly higher compared with patients with obstructive CAD. Independent factors associated with a positive exercise test in patients with no obstructive CAD are an increase in total cholesterol (multivariate regression logistic analysis).

A novel numerical model of combination levels of C-peptide and insulin in coronary artery disease risk prediction

OBJECTIVE

Insulin resistance is a major risk factor for coronary artery disease (CAD). The C-peptide-to-insulin ratio (C/I) is associated with hepatic insulin clearance and insulin resistance. The current study was designed to establish a novel C/I index (CPIRI) model and provide early risk assessment of CAD.

METHODS

A total of 865 adults diagnosed with new-onset diabetes mellitus (DM) within one year and 54 healthy controls (HC) were recruited to develop a CPIRI model. The CPIRI model was established with fasting C/I as the independent variable and homeostasis model assessment of insulin resistance (HOMA-IR) as the dependent variable. Associations between the CPIRI model and the severity of CAD events were also assessed in 45 hyperglycemic patients with CAD documented via coronary arteriography (CAG) and whom underwent stress echocardiography (SE) and exercise electrocardiography test (EET).

RESULTS

Fasting C-peptide/insulin and HOMA-IR were hyperbolically correlated in DM patients and HC, and log(C/I) and log(HOMA-IR) were linearly and negatively correlated. The respective correlational coefficients were -0.83 (p < 0.001) and -0.76 (p < 0.001). The equations CPIRI(DM) = 670/(C/I)2.24 + 0.25 and CPIRI(HC) = 670/(C/I)2.24 - 1 (F = 1904.39, p < 0.001) were obtained. Patients with insulin resistance exhibited severe coronary artery impairment and myocardial ischemia. In CAD patients there was no significant correlation between insulin resistance and the number of vessels involved.

CONCLUSIONS

CPIRI can be used to effectively evaluate insulin resistance, and the combination of CPIRI and non-invasive cardiovascular examination is of great clinical value in the assessment of CAD.