Distribution of coronary calcifications in patients with suspected coronary heart disease

Usefulness of Coronary Artery Calcium Score to Rule Out Obstructive Coronary Artery Disease Before Transcatheter Aortic Valve Implantation

Pretranscatheter aortic valve implantation (pre-TAVI) coronary evaluation using computed tomography coronary angiography (CTA) remains suboptimal. We aimed to evaluate whether coronary artery calcium score (CAC) may rule out obstructive coronary artery disease (CAD) pre-TAVI. TAVI candidates (n = 230; mean age 80 ± 8 years), 49% men, underwent preprocedural CTA and invasive coronary angiography. Obstructive CAD was defined as luminal diameter stenosis of ≥50% of left main or 3 major vessels ≥70%. Vessels with coronary stents or bypass were excluded. CAC score was calculated using the Agatston method. Receiver operating characteristic was applied to establish the CAC threshold for obstructive CAD. Multivariable analysis with adjustment for clinical covariates was applied. Net reclassification for nonobstructive disease using CAC score was calculated among nondiagnostic CT scans. Median CAC score was 1,176 (interquartile range 613 to 1,967). Receiver operating characteristic analysis showed high negative predictive value (NPV) for obstructive CAD as follows: left main CAC score 252, NPV 99%; left anterior descending CAC score 250, NPV 97%; left circumflex CAC score 297, NPV 92%; and right coronary artery CAC score 250, NPV 91%. Multivariate analysis showed the highest tertile of CAC score (≥1,670) to be an independent predictor of obstructive CAD (odds ratio 10.7, 95% confidence interval 4.6 to 25, p <0.001). Among nondiagnostic CTA, net reclassification showed reclassification of 76%, 13%, 45%, and 34% of left main, left anterior descending, left circumflex, and right coronary artery for nonobstructive CAD, respectively. In conclusion, CAC score cutoffs can be used to predict nonobstructive CAD. Implementing CAC score on pre-TAVI imaging can reduce a significant proportion of invasive coronary angiography.

Coronary calcium scoring assessed on native screening chest CT imaging as predictor for outcome in COVID-19: An analysis of a hospitalized German cohort

BACKGROUND

Since the outbreak of the COVID-19 pandemic, a number of risk factors for a poor outcome have been identified. Thereby, cardiovascular comorbidity has a major impact on mortality. We investigated whether coronary calcification as a marker for coronary artery disease (CAD) is appropriate for risk prediction in COVID-19.

METHODS

Hospitalized patients with COVID-19 (n = 109) were analyzed regarding clinical outcome after native computed tomography (CT) imaging for COVID-19 screening. CAC (coronary calcium score) and clinical outcome (need for intensive care treatment or death) data were calculated following a standardized protocol. We defined three endpoints: critical COVID-19 and transfer to ICU, fatal COVID-19 and death, composite endpoint critical and fatal COVID-19, a composite of ICU treatment and death. We evaluated the association of clinical outcome with the CAC. Patients were dichotomized by the median of CAC. Hazard ratios and odds ratios were calculated for the events death or ICU or a composite of death and ICU.

RESULTS

We observed significantly more events for patients with CAC above the group's median of 31 for critical outcome (HR: 1.97[1.09,3.57], p = 0.026), for fatal outcome (HR: 4.95[1.07,22.9], p = 0.041) and the composite endpoint (HR: 2.31[1.28,4.17], p = 0.0056. Also, odds ratio was significantly increased for critical outcome (OR: 3.01 [1.37, 6.61], p = 0.01) and for fatal outcome (OR: 5.3 [1.09, 25.8], p = 0.02).

CONCLUSION

The results indicate a significant association between CAC and clinical outcome in COVID-19. Our data therefore suggest that CAC might be useful in risk prediction in patients with COVID-19.

Predictive value of coronary calcifications for future cardiac events in asymptomatic patients: underestimation of risk in asymptomatic smokers

Coronary calcification (CAC) is an established marker for coronary atherosclerosis and has a highly specific predictive value for cardiovascular events. This study aimed to determine the predictive value in the specific group of asymptomatic smokers in comparison to non-smokers. We included 1432 asymptomatic individuals (575 women, 857 men, age 59.2 ± 7.7 years.) in this study. Coronary calcification was calculated by multi-slice computed tomography following a standardized protocol including calcium score (CS). Coronary risk factors were determined at inclusion. After mean observation time of 76.3 ± 8.5 months the patients were contacted and evaluated for cardiovascular events (myocardial infarction, cardiac death and revascularisation). Mean CS was 231 ± 175 in smokers and 239 ± 188 in non-smokers. Cardiovascular events were found in 14.9% of our patients and there were significantly more events in smokers (119 events, 8.3%) than in non-smokers (94 events, 6.6%, p = 0.001). CS > 400 showed a hazard ratio for future cardiac events of 5.1 (95% CI 4.3-7.6) in smokers and 4.4 (95% CI 3.4-6.2) in non-smokers, p = 0.01. Also in smokers determination of CAC is a valuable predictor of future cardiovascular events. In our study smokers showed throughout all score groups a significantly higher risk compared to non-smokers with equal CS. Therefore, CS may underestimate the risk for future cardiac events in smokers compared to non-smokers.

Long-term prognostic impact of non-invasive follow-up with computed tomography angiography in patients with left main coronary artery stenting

BACKGROUND

Left main coronary artery (LMCA) stenting is an evolving technique. Whether follow-up computed tomography angiography (CTA) might have clinical impact in these patients is controversial. The aim of present study is to compare clinical outcomes of patients with LMCA stenting followed with CTA versus patients with conventional clinical follow-up.

METHODS

From 2003 to 2014 all consecutive patients with unprotected LMCA stenosis treated with single DES implantation were prospectively included. Since 2009 all patients underwent CTA at 6-month after LMCA stenting. Therefore, the non-CTA group included all patients treated from 2003 to 2009 and the CTA group included patients treated from 2009 to 2014. Patients with 6-month cardiac events, renal dysfunction or atrial fibrillation were excluded. All patients underwent at least 2-year clinical follow-up. The primary endpoint was a composite of cardiac death, nonfatal myocardial infarction, and LMCA revascularization.

RESULTS

A total of 236 patients were included (119 in the non-CTA and 117 in the CTA group). Nine event-free patients presented with in-stent restenosis as assessed by CTA at 6 months; 5 had angiographic confirmation and were revascularized. At 2 years, the primary end-point was observed in 15.1% and 7.3% of patients of the non-CTA and CTA groups, respectively (P=0.07). All-cause mortality was higher in the non-CTA group (8.4% vs. 2.6%; P=0.05). Euroscore and CTA were found independent predictors of the primary end-point in the multivariate analysis.

CONCLUSIONS

Elective 6-month CTA after LMCA stenting is associated with better outcomes compared to conventional clinical follow-up.