Heart rate adjustments and analysis of recovery patterns of ST-segment depression in type 2 diabetes

Screening for Asymptomatic Coronary Artery Disease via Exercise Stress Testing in Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Objectives: This meta-analysis aims to investigate the diagnostic value of exercise stress testing (EST) for asymptomatic coronary artery disease (CAD) among patients with type 2 diabetes mellitus (T2DM) and to ascertain the influence of different variables on the sensitivity and specificity of EST. Background: Asymptomatic CAD occurs in >1 in five diabetes mellitus patients, and it is associated with an increased risk of complications. Methods for screening asymptomatic CAD in T2DM patients are still not unified. Methods: MEDLINE (via Ovid), Embase (via Ovid), Cochrane Library, SCOPUS, PubMed, Ovid, EBSCO ASP, and Web of Science were systematically searched on June 8 and 9, 2021, for diagnostic cohort and case-control studies. We included studies that used EST to screen for CAD in asymptomatic patients with T2DM, and that used coronary angiography to diagnose CAD and had reported the basic diagnostic indicators. The Quality Assessment of Diagnostic Accuracy Studies 2 tool was used to assess study quality. The combined effect sizes were calculated by overall analysis and multiple variable effects were explored by regression analysis and subgroup analysis. Results: Nine groups of data from eight diagnostic cohort studies, totaling 515 participants, were included. Included studies showed a low risk of bias in most items, except for flow and timing. The combined sensitivity and specificity of EST for asymptomatic CAD in patients with T2DM were 55 (48 to 61%) and 66 (61 to 70%), respectively. When non-diagnostic tests were excluded, sensitivity increased to 73 (56 to 88%). The proportion receiving angiography also significantly affected sensitivity. No significant difference was found in the duration of diabetes or other additional risk factors. Conclusions: EST is a tool of moderate sensitivity and specificity to be used for the initial screening of asymptomatic CAD in T2DM. It has the advantage of being non-invasive, relatively inexpensive, easily available in most settings, and has no radiation associated with its use. Additional research with higher quality studies in which tests that are non-diagnostic are included and flow and timing is described clearly, will be important to further our understanding of EST for asymptomatic CAD detection in patients with T2DM. Systematic review registration: PROSPERO CRD42021259555.

ST/HR variables in firefighter exercise ECG - relation to ischemic heart disease

Exercise electrocardiography (ExECG) is regularly performed by Swedish firefighters by law. Heart rate-corrected analysis of ST segment variables (ST/HR) has shown improved prediction of ischemic heart disease (IHD) compared to ST depression alone. This has not previously been extensively studied in asymptomatic persons with a low probability of IHD. We therefore evaluated the predictive performance of ST/HR analysis in firefighter ExECG. ExECG was studied in 521 male firefighters. During 8.4 ± 2.1 years, 2.3% (n = 12) were verified with IHD by catheterization or myocardial scintigraphy (age 51.5 ± 5.5 years) and were compared with firefighters without imaging proof of IHD (44.2 ± 10.1 years). The predictive value of ST depression, ST/HR index, ST/HR slope, and area and rotation of the ST/HR loop was calculated as age-adjusted odds ratios (OR), in 10 ECG leads. Predictive accuracy was analyzed with receiver operating characteristics (ROC) analysis. ST/HR index ≤-1.6 μV/bpm and ST/HR slope ≤-2.4 μV/bpm were associated with increased IHD risk in three individual leads (all OR > 1.0, P < 0.05). ST/HR loop area lower than the fifth percentile of non-IHD subjects indicated IHD risk in V4, V5, aVF, II, and -aVR (P < 0.05). ST depression ≤-0.1 mV was associated with IHD only in V4 (OR, 9.6, CI, 2.3-40.0). ROC analysis of each of these variables yielded areas under the curve of 0.72 or lower for all variables and leads. Clockwise-rotated ST/HR loops was associated with increased risk in most leads compared to counterclockwise rotation. The limited clinical value of ExECG in low-risk populations was emphasized, but if performed, ST/HR analysis should probably be given more importance.

Long-term follow-up of a hospital-based, multi-intervention programme in type 2 diabetes mellitus: impact on cardiovascular events and death

Objective

To report the long-term impact on cardiovascular (CV) outcomes and mortality of a 2-year hospital-based multi-interventional care programme as compared with general practitioner (GP)-provided standard care.

Methods

Patients with type 2 diabetes with ≥ 1 additional CV risk factor were randomized to 2 years of specialist-based, multi-intervention comprising lifestyle modification and specific pharmacological treatment, or GP-based standard care. After the 2-year intervention period, all participants returned to pre-study care, but were followed up for CV outcomes and mortality. The primary outcome was time to any first severe CV event or death.

Results

A total of 120 patients (31 women) were enrolled in the study. During the mean ± SD observational period of 8.7 ± 2.0 years, 27 patients (16 and 11 in the multi-intervention and standard care groups, respectively) experienced at least one primary outcome event, with a hazard ratio (HR) if allocated to the multi-intervention group of 1.73 (95% confidence interval (CI) 0.80, 3.75). The HR for total mortality was 1.82 (95% CI 0.66, 5.01).

Conclusions

Hospital-based multi-intervention in patients with type 2 diabetes mellitus improved long-term glycaemic control, but failed to reduce CV outcomes and deaths.

Clinical trials.gov id: NCT00133718.

Neutral impact on systolic and diastolic cardiac function of 2 years of intensified multi-intervention in type 2 diabetes: the randomized controlled Asker and Bærum Cardiovascular Diabetes (ABCD) study

BACKGROUND

Patients with type 2 diabetes (T2D) are prone to develop preclinical myocardial dysfunction, but no single strategy to prevent progression to heart failure has been established. We aimed to assess whether intensified global cardiovascular (CV) risk factor control would improve left ventricular (LV) systolic and diastolic function as compared with standard of care.

METHODS

A total of 100 patients with ≥1 CV risk factor (29% female, mean ± SD age 58 ± 10 years, LV ejection fraction 63 ± 8%, 16% with LV diastolic dysfunction) were randomized to 2 years of intensified CV risk multi-intervention (INT, n = 50) or standard care (STAND, n = 50). Echocardiography, including tissue Doppler imaging, and maximum exercise test were performed at baseline and study end. Multi-intervention comprised lifestyle intervention and pharmacologic treatment to reach strict prespecified CV risk factor goals, whereas STAND group received current guideline care.

RESULTS

Greater reductions were observed for hemoglobin A1c and total cholesterol in the INT group (P < .001 and P = .021, respectively), whereas blood pressure reduction was similar. Work capacity increased in INT and decreased in STAND (P = .014). There was no significant between-group difference in the change in any of the echocardiographic parameters.

CONCLUSIONS

Two years of intensified multi-intervention in patients with T2D improved work capacity and glycemic and lipid control and had no significant benefit or harm on resting cardiac function.

Interleukin-6 and activin A are independently associated with cardiovascular events and mortality in type 2 diabetes: the prospective Asker and Bærum Cardiovascular Diabetes (ABCD) cohort study

Background

Novel and robust cardiovascular (CV) markers are needed to improve CV morbidity and mortality risk prediction in type 2 diabetes (T2D). We assessed the long term predictive value of 4 novel CV risk markers for major CV events and mortality.

Methods

We included patients with T2D who had cytokines (interleukin [IL]-6 and activin A [actA]), a maximum stress ECG test (evaluated by the normalization pattern in early recovery phase) and echocardiography (evaluated by a measure of the left ventricular filling pressure - E/Em) assessed at baseline. The primary endpoint was time to first of any of the following events: myocardial infarction, stroke, hospitalization for unstable angina pectoris and death. All outcomes were adjudicated by independent experts. We used Cox proportional hazard modeling, Harrell C-statistic and the net reclassification improvement (NRI) to assess the additional value beyond conventional markers (age, gender, prior CV disease, HDL, creatinine, diastolic BP, microalbuminuria).

Results

At baseline the study cohort (n = 135, mean age/diabetes duration/HbA1c: 59 yrs/7 yrs/7.6% [59 mmol/mol], 26% females) had moderate elevated CV risk (42% microalbuminuria, mean Framingham 10 year CV-risk 9.6%). During 8.6 yrs/1153.7 person years, 26 patients experienced 36 events. All 4 novel risk markers were significantly associated with increased risk of the primary endpoint, however, only IL-6 and actA improved C-statistic and NRI (+0.119/43.2%, +0.065/20.3% respectively) compared with the conventional CV risk factors.

Conclusions

IL-6 and actA may provide prognostic information on CV events and mortality in T2D beyond conventional CV risk factors.

Trial registration

ClinicalTrials.gov: NCT00133718

Exercise-induced ST-segment depression in inferior leads during treadmill exercise testing and coronary artery disease

The exercise electrocardiogram is a commonly used non-invasive and inexpensive method for detection of electrocardiogram (ECG) changes secondary to myocardial ischemia. Reversible ST-segment depression is the characteristic finding associated with exercise-induced, demand-driven ischemia in patients with significant coronary obstruction but no flow limitation at rest. The exercise-induced ST-segment depression in inferior leads has been questioned and it has been reported that lead V5 alone consistently outperforms the inferior leads and the combination of lead V5 with II, because lead II has a high false-positive rate. A review of the 12-lead visual electrocardiographic interpretations confirmed that changes isolated to the inferior leads were rare in patients, who had no diagnostic Q waves. Considering the sum of ST-segment depression or the most depression in the three leads representing the three main areas of the myocardium (II, V2, and V5) did not improve the diagnostic capacity of the test. A case is presented to illustrate how in a patient, the ST-segment depression in inferior leads during exercise testing is related with significant coronary artery disease. We present a case of exercise-induced ST-segment depression in inferior leads in a 52 year-old Italian man. This experience demonstrates that ST-segment depression in inferior leads during the exercise testing can have a diagnostic significance.