Intravascular ultrasound correlates of corrected TIMI framecount

The effect of prior COVID-19 infection on coronary microvascular dysfunction

BACKGROUND

Thrombolysis in Myocardial Infarction Frame Count (TFC) is an index that provides a quantitative evaluation of coronary microvascular dysfunction. In this study, we aimed to examine the effect of COVID-19 infection on TFC in patients admitted with chest pain and dyspnoea after COVID-19 disease and had abnormal findings in myocardial perfusion scintigraphy.

METHODS

For this single-center retrospective study, patients with and without a history of COVID-19 who were underwent coronary angiography for abnormal findings in myocardial perfusion scintigraphy between January 1, 2021 and June 30, 2021 were analysed. Patients were divided into two groups as patients with COVİD-19 history and those without. After exclusion criteria, patients with adequate angiographic monitoring and data were included in the study.

RESULTS

A total of 210 patients, 48 with a history of COVID-19, were included in the study. The mean age was ±55 10 years, and 122 (58%) patients were women. In patients with a history of COVID-19, TFC was significantly higher in the LAD (p < 0.001) and LCx (p < 0.001) arteries and RCA TFC (p = 0.223) was similar in both groups. In the linear mix model, male gender (β = 2.38, 95% CI = 1.26-3.51, p < 0.001) and history of COVID-19 (β = 1.51, 95% CI = 0.49-2.53, p = 0.004) were significantly associated with TFC.

CONCLUSION

TFC may be elevated due to coronary microvascular dysfunction in patients with a history of COVID-19.

Sex and Gender Differences in Ischemic Heart Disease: Endocrine Vascular Disease Approach (EVA) Study Design

Improvements in ischemic heart disease (IHD) management have been unbalanced between sexes, with coronary microvascular dysfunction considered the likely underlying reason. The Endocrine Vascular disease Approach (EVA) is an observational study (Clinicaltrial.gov NCT02737982) aiming to assess sex and gender interactions between coronary circulation, sexual hormones, and platelet function. Consecutive patients with IHD undergoing coronary angiography will be recruited: (1) to assess sex and gender differences in angiographic reperfusion indexes; (2) to evaluate the effects of estrogen/androgen on sex-related differences in myocardial ischemia; (3) to investigate the platelet biology differences between men and women with IHD; (4) to verify sex- and gender-driven interplay between response to percutaneous coronary intervention, platelets, sex hormones, and myocardial damage at baseline and its impact on 12-month outcomes. The integration of sex and gender in this translational project on IHD will contribute to the identification of new targets for further innovative clinical interventions.

TIMI frame count and adverse events in women with no obstructive coronary disease: a pilot study from the NHLBI-sponsored Women's Ischemia Syndrome Evaluation (WISE)

BACKGROUND

TIMI frame count (TFC) predicts outcomes in patients with obstructive coronary artery disease (CAD); it remains unclear whether TFC predicts outcomes in patients without obstructive CAD.

METHODS

TFC was determined in a sample of women with no obstructive CAD enrolled in the Women's Ischemia Syndrome Evaluation (WISE) study. Because TFC is known to be higher in the left anterior descending artery (LAD), TFC determined in the LAD was divided by 1.7 to provide a corrected TFC (cTFC).

RESULTS

A total of 298 women, with angiograms suitable for TFC analysis and long-term (6-10 year) follow up data, were included in this sub-study. Their age was 55±11 years, most were white (86%), half had a history of smoking, and half had a history of hypertension. Higher resting cTFC was associated with a higher rate of hospitalization for angina (34% in women with a cTFC >35, 15% in women with a cTFC ≤35, P<0.001). cTFC provided independent prediction of hospitalization for angina after adjusting for many baseline characteristics. In this cohort, resting cTFC was not predictive of major events (myocardial infarction, heart failure, stroke, or all-cause death), cardiovascular events, all-cause mortality, or cardiovascular mortality.

CONCLUSIONS

In women with signs and symptoms of ischemia but no obstructive CAD, resting cTFC provides independent prediction of hospitalization for angina. Larger studies are required to determine if resting TFC is predictive of major events in patients without obstructive coronary artery disease.

Use of the TIMI frame count in the assessment of coronary artery blood flow and microvascular function over the past 15 years

Since its introduction, the TIMI frame count method has contributed to the understanding of the pathophysiology of coronary artery disease. In this article, the evolution of the TFC method and its applicability in the assessment of various therapeutic modalities are described.

Coronary Angiography for Follow-up of Heart Transplant Recipients: Insights From TIMI Frame Count and TIMI Myocardial Perfusion Grade

BACKGROUND

The aim of this study was to evaluate the course of Thrombolysis in Myocardial Infarction (TIMI) frame count (TIMI FC) and myocardial perfusion grade (TIMI MPG) in heart transplant recipients and whether these parameters could predict mortality.

METHODS

Sixty-two heart transplant recipients were enrolled in this study. All patients had coronary angiography at baseline and at 1 year, which were evaluated for TIMI FC and TIMI MPG. Also, 50 vessels in 35 patients were analyzed with volumetric intravascular ultrasound (IVUS) at baseline and at 1 year. Rejection episodes and mortality were recorded during the follow-up period.

RESULTS

The mean follow-up interval was 51.5 +/- 17.2 months (range 12.2 to 78.4 months). TIMI FCs of all three coronary arteries and global TIMI FC (gTIMI FC) significantly increased from baseline during the first year (p < 0.0001). TIMI MPG deteriorated significantly (p < 0.0001 for left anterior descending and circumflex coronary arteries, p = 0.002 for right coronary artery). There was no correlation between changes in TIMI FC and progression of transplant vasculopathy as assessed by IVUS. Episodes of Grade > or = 3A rejection were significantly more frequent in the stable gTIMI FC group (p = 0.03). Mortality rate was significantly higher in the group with increasing gTFC (p = 0.02).

CONCLUSIONS

gTIMI FCs and TIMI FCs of coronary arteries increase, and TIMI MPG gradually deteriorates during the first year after transplantation. Mortality rate is significantly higher in patients whose gTIMI FC increases from baseline. Change in gTIMI FC is a simple quantitative predictor of long-term mortality in heart transplant recipients.