What percent luminal stenosis should be used to define angiographic coronary artery disease for noninvasive test evaluation?

Type 2 diabetes mellitus and coronary artery stenosis: a risk pattern association study

Aim: Cardiovascular diseases (CVD) are the leading cause of death globally. In the condition of type 2 diabetes mellitus (T2DM), the prevalence of CVD increase parallel with the rise of metabolic complication and higher incidence of coronary artery stenosis. The aim of this study was to compare the level of percent stenosis in coronary arteries in patients with coronary artery disease (CAD) with and without T2DM, and to measure the severity of CVD using Gensini score (GS) through angiographic data. Methods: The current study was conducted in tertiary care specialized hospital in Delhi, India. The level of percent stenosis in coronary arteries was compared in patients with CAD with and without T2DM. The patients were divided into two groups: group I included 100 patients with T2DM, and group II included 100 non-diabetic CAD patients who underwent coronary angiography by Judkin’s technique. The severity of CVD was measured by GS through angiographic data. The serum levels of glycated haemoglobin (HbA1c) ≥ 6.5% were considered diabetic. Results: Significant difference was observed in serum HbA1c, and random blood sugar levels between group I and group II were also observed (P ≤ 0.001). Serum HbA1c shows a significant positive association with GS (r = 0.36, P = 0.007). Conclusions: The study shows a significant level of stenosis in coronary arteries of CAD diabetic patients. However, further prospective analysis of a larger population size will be needed to strengthen the findings and the significant association.

Timing and Outcomes After Coronary Angiography Following Out-of-Hospital Cardiac Arrest Without Signs of ST-Segment Elevation Myocardial Infarction

BACKGROUND

There is broad consensus that resuscitated out-of-hospital cardiac arrest (OHCA) patients with ST-segment elevation myocardial infarction (STEMI) should receive immediate coronary angiography (CAG); however, factors that guide patient selection and optimal timing of CAG for post-arrest patients without evidence of STEMI remain incompletely described.

OBJECTIVE

We sought to describe the timing of post-arrest CAG in actual practice, patient characteristics associated with decision to perform immediate vs. delayed CAG, and patient outcomes after CAG.

METHODS

We conducted a retrospective cohort study at seven U.S. academic hospitals. Resuscitated adult patients with OHCA were included if they presented between January 1, 2015 and December 31, 2019 and received CAG during hospitalization. Emergency medical services run sheets and hospital records were analyzed. Patients without evidence of STEMI were grouped and compared based on time from arrival to CAG performance into "early" (≤ 6 h) and "delayed" (> 6 h).

RESULTS

Two hundred twenty-one patients were included. Median time to CAG was 18.6 h (interquartile range [IQR] 1.5-94.6 h). Early catheterization was performed on 94 patients (42.5%) and delayed catheterization was performed on 127 patients (57.5%). Patients in the early group were older (61 years [IQR 55-70 years] vs. 57 years [IQR 47-65] years) and more likely to be male (79.8% vs. 59.8%). Those in the early group were more likely to have clinically significant lesions (58.5% vs. 39.4%) and receive revascularization (41.5% vs. 19.7%). Patients were more likely to die in the early group (47.9% vs. 33.1%). Among survivors, there was no significant difference in neurologic recovery at discharge.

CONCLUSIONS

OHCA patients without evidence of STEMI who received early CAG were older and more likely to be male. This group was more likely to have intervenable lesions and receive revascularization.

Complete Revascularization and One-Year Survival with Good Neurological Outcome in Patients Resuscitated from an Out-of-Hospital Cardiac Arrest

Background. The survival benefit of complete versus infarct-related artery (IRA)-only revascularization during the index hospitalization in patients resuscitated from an out-of-hospital cardiac arrest (OHCA) with multivessel disease is unknown. Methods. We considered all the OHCA patients prospectively enrolled in the Lombardia Cardiac Arrest Registry (Lombardia CARe) from 1 January 2015 to 1 May 2021 who underwent coronary angiography (CAG) at the Fondazione IRCCS Policlinico San Matteo (Pavia). Patients’ prehospital, angiographical and survival data were reviewed. Results. Out of 239 patients, 119 had a multivessel coronary disease: 69% received IRA-only revascularization, and 31% received a complete revascularization: 8 during the first procedure and 29 in a staged-procedure after a median time of 5 days [IQR 2.5−10.3]. The complete revascularization group showed significantly higher one-year survival with good neurological outcome than the IRA-only group (83.3% vs. 30.4%, p < 0.001). After correcting for cardiac arrest duration, shockable presenting rhythm, peak of Troponin-I, creatinine on admission and the need for circulatory support, complete revascularization was independently associated with the probability of death and poor neurological outcome [HR 0.3 (95%CI 0.1−0.8), p = 0.02]. Conclusions. This observation study shows that complete myocardial revascularization during the index hospitalization improves one-year survival with good neurological outcome in patients resuscitated from an OHCA with multivessel coronary disease.

Clinical factors associated with significant coronary lesions following out-of-hospital cardiac arrest

OBJECTIVES

Out-of-hospital cardiac arrest (OHCA) afflicts >350,000 people annually in the United States. While postarrest coronary angiography (CAG) with percutaneous coronary intervention (PCI) has been associated with improved survival in observational cohorts, substantial uncertainty exists regarding patient selection for postarrest CAG. We tested the hypothesis that symptoms consistent with acute coronary syndrome (ACS), including chest discomfort, prior to OHCAs are associated with significant coronary lesions identified on postarrest CAG.

METHODS

We conducted a multicenter retrospective cohort study among eight regional hospitals. Adult patients who experienced atraumatic OHCA with successful initial resuscitation and subsequent CAG between January 2015 and December 2019 were included. We collected data on prehospital documentation of potential ACS symptoms prior to OHCA as well as clinical factors readily available during postarrest care. The primary outcome in multivariable regression modeling was the presence of significant coronary lesions (defined as >50% stenosis of left main or >75% stenosis of other coronary arteries).

RESULTS

Four-hundred patients were included. Median (interquartile range) age was 59 (51-69) years; 31% were female. At least one significant stenosis was found in 62%, of whom 71% received PCI. Clinical factors independently associated with a significant lesion included a history of myocardial infarction (adjusted odds ratio [aOR] = 6.5, [95% confidence interval {CI} = 1.3 to 32.4], p = 0.02), prearrest chest discomfort (aOR = 4.8 [95% CI = 2.1 to 11.8], p ≤ 0.001), ST-segment elevations (aOR = 3.2 [95% CI = 1.7 to 6.3], p < 0.001), and an initial shockable rhythm (aOR = 1.9 [95% CI = 1.0 to 3.4], p = 0.05).

CONCLUSIONS

Among survivors of OHCA receiving CAG, history of prearrest chest discomfort was significantly and independently associated with significant coronary artery lesions on postarrest CAG. This suggests that we may be able to use prearrest symptoms to better risk stratify patients following OHCA to decide who will benefit from invasive angiography.

Standardizing the Definition and Analysis Methodology for Complete Coronary Artery Revascularization

Guideline‐based medical therapy is the foundation of treatment for individuals with coronary artery disease. However, revascularization with either percutaneous coronary intervention or coronary artery bypass grafting may be beneficial in patients with acute coronary syndromes, refractory symptoms, or in other specific scenarios (eg, left main disease and heart failure). While the goal of percutaneous coronary intervention and coronary artery bypass grafting is to achieve complete revascularization, anatomical and ischemic definitions of complete revascularization and their methodology for assessment remain highly variable. Such lack of consensus invariably contributes to the absence of standardized approaches for invasive treatment of coronary artery disease. Herein, we propose a novel, comprehensive, yet pragmatic algorithm with both anatomical and ischemic parameters that aims to provide a systematic method to assess complete revascularization after percutaneous coronary intervention or coronary artery bypass grafting in both clinical practice and clinical trials.

The predictive value of HEART score for acute coronary syndrome and significant coronary artery stenosis

Objective

Rapid determination of acute coronary syndrome (ACS) in the emergency department (ED) is very important for patients presenting with ischemic symptoms. The aim of this study was to determine the predictive value of HEART score for ACS and significant coronary artery stenosis (SCS).

Methods

We retrospectively analyzed data of patients who visited the ED with chest discomfort and were admitted to the cardiology department. Enrolled patients were classified into ACS and non-ACS groups according to their discharge diagnosis. Patients who underwent imaging were further divided into SCS and non-SCS groups according to study results. We compared age, sex, vital signs, risk factors, electrocardiogram, troponin, and HEART score for each group. For ACS and SCS predictive performance, the test characteristics of HEART score was calculated using sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic (ROC) curve analysis.

Results

Of 207 patients, 112 had ACS. Among enrolled patients, 155 underwent imaging workup, of whom 67 had SCS. HEART score ≤3 had 93% sensitivity for ACS and 97% for SCS. HEART score ≥7 had 82% specificity for ACS and 83% for SCS. HEART score area under ROC curve for ACS was 0.706 (95% confidence interval, 0.627–0.776) and 0.737 (95% confidence interval, 0.660–0.804) for SCS.

Conclusion

HEART score was a fair predictor of ACS and SCS in ED patients who presented with chest symptoms and were admitted to the cardiology department. The predictive power of HEART score was better for SCS than for ACS.

Factors associated with left ventricular reverse remodelling after percutaneous coronary intervention in patients with left ventricular systolic dysfunction

Percutaneous coronary intervention (PCI) is sometimes considered as an alternative therapeutic strategy to surgical revascularization in patients with coronary artery disease (CAD) and reduced left ventricular ejection fraction (LVEF). However, the types or conditions of patients that receive the clinical benefit of left ventricular reverse remodelling (LVRR) remain unknown. The purpose of this study was to investigate the determinants of LVRR following PCI in CAD patients with reduced LVEF. From 4394 consecutive patients who underwent PCI, a total of 286 patients with reduced LV systolic function (LVEF < 50% at initial left ventriculography) were included in the analysis. LVRR was defined as LV end-systolic volume reduction ≥ 15% and improvement of LVEF ≥ 10% at 6 months follow-up left ventriculography. Patients were divided into LVRR (n = 63) and non-LVRR (n = 223) groups. Multivariate logistic regression analysis revealed that unprotected left main coronary artery (LMCA) intervention was significantly associated with LVRR (P = 0.007, odds ratios [OR] 4.70, 95% confidence interval [CI] 1.54-14.38), while prior PCI (P = 0.001, OR 0.35, 95% CI 0.19-0.66), presence of in-stent restenosis (P = 0.016, OR 0.32, 95% CI 0.12-0.81), and presence of de-novo stenosis (P = 0.038, OR 0.36, 95% CI 0.14-0.95) were negatively associated with LVRR. These data suggest the potential prognostic benefit of unprotected LMCA intervention for LVRR and importance of angiographic follow-up in patients with CAD and LV systolic dysfunction.

Association of Timing of Electrocardiogram Acquisition After Return of Spontaneous Circulation With Coronary Angiography Findings in Patients With Out-of-Hospital Cardiac Arrest

IMPORTANCE

Electrocardiography (ECG) is an important tool to triage patients with out-of-hospital cardiac arrest (OHCA) after return of spontaneous circulation (ROSC). An immediate coronary angiography after ROSC is recommended only in patients with an ECG that is diagnostic of ST-segment elevation myocardial infarction (STEMI). To date, the benefit of this approach has not been demonstrated in patients with a post-ROSC ECG that is not diagnostic of STEMI.

OBJECTIVE

To assess whether the time from ROSC to ECG acquisition is associated with the diagnostic accuracy of ECG for STEMI.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, multicenter cohort study (the Post-ROSC Electrocardiogram After Cardiac Arrest study) analyzed consecutive patients older than 18 years who were resuscitated from OHCA between January 1, 2015, and December 31, 2018, and were admitted to 1 of the 3 participating centers in Europe (Pavia, Italy; Lugano, Switzerland; and Vienna, Austria).

EXPOSURE

Only patients who underwent coronary angiography during hospitalization and who acquired a post-ROSC ECG before the angiography were enrolled. Patients with a nonmedical cause of OHCAs were excluded.

MAIN OUTCOMES AND MEASURES

The primary end point was false-positive ECG findings, defined as the percentage of patients with post-ROSC ECG findings that met STEMI criteria but who did not show obstructive coronary artery disease on angiography that was worthy of percutaneous coronary angioplasty.

RESULTS

Of 586 consecutive patients who were admitted to the 3 participating centers, 370 were included in the analysis (287 men [77.6%]; median age, 62 years [interquartile range, 53-70 years]); 121 (32.7%) were enrolled in the participating center in Pavia, Italy; 38 (10.3%) in Lugano, Switzerland; and 211 (57.0%) in Vienna, Austria. The percentage of false-positive ECG findings in the first tertile of ROSC to ECG time (≤7 minutes) was significantly higher than that in the second (8-33 minutes) and third (>33 minutes) tertiles: 18.5% in the first tertile vs 7.2% in the second (odds ratio [OR], 0.34; 95% CI, 0.13-0.87; P = .02) and 5.8% in the third (OR, 0.27; 95% CI, 0.15-0.47; P < .001). These differences remained significant when adjusting for sex (≤7 minutes: reference; 8-33 minutes: OR, 0.32; 95% CI, 0.12-0.85; P = .02; >33 minutes: OR, 0.26; 95% CI, 0.14-0.47; P < .001), age (≤7 minutes: reference; 8-33 minutes: OR, 0.34; 95% CI, 0.13-0.89; P = .03; >33 minutes: OR, 0.27; 95% CI, 0.15-0.46; P < .001), number of segments with ST-elevation (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.15-0.81; P = .01; >33 minutes: OR, 0.28; 95% CI, 0.15-0.52; P < .001), QRS duration (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.14-0.87; P = .02; >33 minutes: OR, 0.27; 95% CI, 0.15-0.48; P < .001), heart rate (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.93; P = .04; >33 minutes: OR, 0.29; 95% CI, 0.15-0.55; P < .001), epinephrine administered (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.98; P = .045; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001), shockable initial rhythm (≤7 minutes: reference; 8-33 minutes: OR, 0.35; 95% CI, 0.13-0.96; P = .04; >33 minutes: OR, 0.26; 95% CI, 0.15-0.46; P < .001), and 3 or more shocks administered (≤7 minutes: reference; 8-33 minutes: OR, 0.36; 95% CI, 0.13-1.00; P = .05; >33 minutes: OR, 0.27; 95% CI, 0.16-0.48; P < .001) in bivariable analyses.

CONCLUSIONS AND RELEVANCE

This study suggests that early ECG acquisition after ROSC in patients with OHCA is associated with a higher percentage of false-positive ECG findings for STEMI. It may be reasonable to delay post-ROSC ECG by at least 8 minutes after ROSC or repeat the acquisition if the first ECG is diagnostic of STEMI and is acquired early after ROSC.

Lewis blood group phenotype vis-a-vis biochemical and physiological parameters of coronary artery disease: A study in North Indian population

BACKGROUND:

Many studies have proposed the lack of Lewis antigen as a marker for coronary artery disease (CAD); on the contrary, some of the studies found no association in this regard. This study aims to assess the association of the expression of Lewis antigen as an independent risk factor for CAD separately in males and females.

MATERIALS AND METHODS:

In this cross-sectional observational study, patients with angiographically proven CAD were taken as test group, and angiographically, negative patients were included as a control group. The individuals were examined for established CAD risk factor and Lewis antigen expression on red cell. Red cell Lewis phenotyping was done using microcolumn gel agglutination technology. Statistical tests were applied to see the association between lack of Lewis antigen expression and CAD.

RESULTS:

Of these 232 patients included in the study, 161 patients had more than 50% luminal stenosis in a major epicardial artery on coronary angiography (Test Group), and 71 were normal on angiography (Control Group). When males and females were considered together, there was an increased frequency of Lewis-negative phenotype among the angiography-positive group (26.7%) as compared to angiography normal control group (16.9 %), though was not statistically significant (P = 0.19). When males and females were segregated in multivariate analysis, Le (a-b-) females had a higher incidence of CAD (P = 0.03) with the odds ratio of 4.97, though an association was not found significant in males (P = 0.71).

CONCLUSION:

The association between Lewis phenotypes and CAD was not significant in males and in among the overall study population, but this association was statistically significant in females. Further studies based on a larger sample size may substantiate as well as delineate the possible hypotheses.

Monocyte and macrophage subtypes as paired cell biomarkers for coronary artery disease

NEW FINDINGS

What is the central question of this study? Are circulating monocyte markers correlated with their derived macrophage polarization patterns and coronary artery disease severity? What is the main finding and its importance? There was an inverse relationship between circulating CD16⁺ monocytes (high) and M2 macrophages (low) that marked coronary disease severity, and the differences in polarization of macrophages were seen despite a week of cell culture ex vivo. This study highlights the importance, and potential prognostic implications, of circulating monocyte and descendant macrophage phenotypes in coronary artery disease.

ABSTRACT

Monocytes and macrophages are central to atherosclerosis, but how they combine to mark progression of human coronary artery disease (CAD) is unclear. We tested whether patients' monocyte subtypes paired with their derived macrophage profiles were correlated with extent of CAD. Peripheral blood was collected from 40 patients undergoing cardiac catheterization, and patients were categorized as having no significant CAD, single vessel disease or multivessel disease according to the number of affected coronary arteries. Mononuclear cells were measured for the monocyte markers CD14 and CD16 by flow cytometry, and separate monocytes were cultured into macrophages over 7 days and measured for the polarization markers CD86 and CD206. At baseline, patients with a greater CAD burden were older, with higher rates of statin, β-blocker and antiplatelet drug use, whereas other characteristics were similar across the spectrum of coronary disease. CD16⁺ (both intermediate and non-classical) monocytes were elevated in patients with single vessel and multivessel disease compared with those without significant CAD (P < 0.05), whereas regulatory M2 macrophages (CD206⁺ ) were decreased in patients with single vessel and multivessel disease (P < 0.001). An inverse relationship between paired CD16⁺ monocytes and M2 macrophages marked CAD severity. On multivariable linear regression, CAD severity was associated, along with age and traditional cardiovascular risk factors, with CD16⁺ monocytes (directly) and M2 macrophages (inversely). Circulating monocytes may influence downstream polarization of lesional macrophages, and these measures of monocyte and macrophage subtypes hold potential as biomarkers in CAD.

Association of MIR-499a expression and seed region variant (rs3746444) with cardiovascular disease in Egyptian patients

BACKGROUND

Circulating microRNAs could be powerful markers of acute myocardial infarction (MI) and its functional genetic variants could increase susceptibility to cardiovascular disease (CVD). The current study aimed to quantify the microRNA (miR)-499a levels in serum of MI patients compared to hypertensive and healthy subjects and to investigate the association of its A/G variant rs3746444 with CVD in a sample of an Egyptian population.

METHODS

Serum miR-499a relative expressions were measured in 110 acute MI patients, 76 hypertensive patients, and 121 healthy controls by Real-time quantitative polymerase chain reaction. MIR-499a genotyping was performed for an additional 107 coronary artery disease patients by Real-time allele discrimination assay.

RESULTS

Acute MI patients showed high relative expression of miR-499a (> 105-fold, p < .001), and it was nearly undetectable in healthy controls and hypertensive patients. It showed an area under the curve of 0.953, with a sensitivity of 97.2% and a specificity of 75.0%. ST-elevation MI (STEMI) patients had higher miR-499a serum levels than patients with Non-STEMI. There was a significant association of MIR-499a variant with acute MI but not with hypertension under all genetic models tested. As a new finding, in overall and stratified analysis, the miR-499a variant was not correlated with its expression profile.

CONCLUSIONS

Circulating miR-499a levels could be a useful biomarker, discriminating acute MI within 12 hours from healthy subjects. Its variant rs3746444 A/G is associated with increased susceptibility to acute MI and CAD in Egyptian population.

Deaths in triathletes: immersion pulmonary oedema as a possible cause

BACKGROUND/AIM

To address the question as to whether immersion pulmonary oedema (IPO) may be a common cause of death in triathlons, markers of swimming-induced pulmonary oedema (SIPO) susceptibility were sought in triathletes' postmortem examinations.

METHODS

Deaths while training for or during triathlon events in the USA and Canada from October 2008 to November 2015 were identified, and postmortem reports requested. We assessed obvious causes of death; the prevalence of left ventricular hypertrophy (LVH); comparison with healthy triathletes.

RESULTS

We identified 58 deaths during the time period of the review, 42 (72.4%) of which occurred during a swim. Of these, 23 postmortem reports were obtained. Five individuals had significant (≥70%) coronary artery narrowing; one each had coronary stents; retroperitoneal haemorrhage; or aortic dissection. 9 of 20 (45%) with reported heart mass exceeded 95th centile values. LV free wall and septal thickness were reported in 14 and 9 cases, respectively; of these, 6 (42.9%) and 4 (44.4%) cases exceeded normal values. 6 of 15 individuals (40%) without an obvious cause of death had excessive heart mass. The proportion of individuals with LVH exceeded the prevalence in the general triathlete population.

CONCLUSIONS

LVH-a marker of SIPO susceptibility-was present in a greater than the expected proportion of triathletes who died during the swim portion. We propose that IPO may be a significant aetiology of death during the swimming phase in triathletes. The importance of testing for LVH in triathletes as a predictor of adverse outcomes should be explored further.

Accuracy of intravascular ultrasound and optical coherence tomography in identifying functionally significant coronary stenosis according to vessel diameter: A meta-analysis of 2,581 patients and 2,807 lesions

INTRODUCTION

Accuracy of intracoronary imaging to discriminate functionally significant coronary stenosis according to vessel diameter remains to be defined.

METHODS

PubMed, Scopus, and Google Scholar were systematically searched for studies assessing diagnostic accuracy (area under the receiver operating characteristic curve [AUC], the primary end point) and sensitivity and specificity (the secondary end points) of minimal luminal area (MLA) or of minimal luminal diameter (MLD) derived from intravascular ultrasound (IVUS) or optical coherence tomography (OCT) to detect functionally significant stenosis as determined with fractional flow reserve (FFR).

RESULTS

Fifteen studies were included, 2 with 110 patients analyzing only left main (LM), 5 with 224 patients and 306 lesions using OCT, and 9 with 1532 patients and 1681 lesions with IVUS. Median MLA for the OCT studies was 1.96 mm(2) (1.85-1.98 mm(2)), 2.9 mm(2) (2.7-3.1 mm(2)) for MLA of all lesions assessed with IVUS, 2.8 mm(2) (2.7-2.9 mm(2)) for lesions with an angiographic diameter >3 mm, 2.4 mm(2) (2.4-2.5 mm(2)) for lesions <3 mm, and 5.4 mm(2) (5.1-5.6 mm(2)) for LM lesions. For OCT-MLA, AUC was 0.80 (0.74-0.86), with a sensitivity of 0.81 (0.74-0.87) and specificity of 0.77 (0.71-0.83), whereas OCT-MLD had an AUC of 0.85 (0.79-0.91), sensitivity of 0.74 (0.69-0.78), and specificity of 0.70 (0.68-0.73). For IVUS-MLA, AUC was 0.78 (0.75-0.81) for all lesions, 0.78 (0.73-0.84) for vessels with a diameter >3 mm, and 0.79 (0.70-0.89) for those with a diameter <3 mm. Left main AUC was 0.97 (0.93-1).

CONCLUSION

Intravascular ultrasound and OCT had modest diagnostic accuracy for identification hemodynamically significant lesions, also with specific cutoff for different diameters. Invasive imaging for assessment of LM severity demonstrated excellent correlation with FFR. What is already known about this subject? Fractional flow reserve represents the criterion standard to evaluate the prognostic value of coronary stenosis, whereas its relationship with IVUS and OCT remains to be assessed. What does this study add? Despite improvement, IVUS and OCT do not predict functional stenosis, even with dedicated cutoff, apart from LM disease. How might this impact on clinical practice? The recent guidelines of myocardial revascularization have stressed the crucial role of FFR before performing percutaneous coronary intervention on LM, whereas intravascular imaging is often exploited to drive revascularization. The present analysis stresses the point that LM percutaneous coronary intervention may be driven only by intravascular imaging, given the high accuracy for significant ischemic lesions, whereas for other vessels, these 2 techniques mirror 2 different aspects.

Comparison of 128-Slice Dual Source CT Coronary Angiography with Invasive Coronary Angiography

BACKGROUND

Coronary artery disease (CAD) is one of the leading cause of the morbidity and mortality in India as well as worldwide and last decade has seen a steep rise in incidence of CAD in India. Direct visualization of the coronary arteries by invasive catheterization still represents the cornerstone of the evaluation of CAD. Cardiac imaging is a challenge of 21 (st) century and is being answered by 128 slice dual source CT as it has good temporal resolution, high scanning speed as well as low radiation dose.

AIM

To assess the diagnostic accuracy of 128-slice dual source CT Cardiac Angiography in comparison with Conventional Catheter Cardiac Angiography.

MATERIALS AND METHODS

Forty patients attending the cardiology OPD with complaint of chest pain and suspected of having CAD were evaluated by CT coronary angiography and conventional invasive Catheter coronary angiography and the results were compared. All patients were checked for serum creatinine and ECG before the angiography. Computed Tomography (CT) coronary angiography was done using SIEMENS 128-slice Dual Source Flash Definition CT Scanner under either Retrospective or Prospective mode depending on the heart rate of the patient. Oral/IV beta-blocker were used whenever required.

RESULTS

Coronary arteries were assessed as per 17- segment AHA model. A total of 600/ 609 segments were evaluable in 40 suspected patients on CT coronary angiography, of which 21 were false positives and 8 were false negatives with specificity of 95.12% and sensitivity and positive predictive value of 95.26% & 88.46% respectively.

CONCLUSION

Non-invasive assessment of CAD is now possible with high accuracy on 128-slice dual source CT scanner.

Usefulness of diastolic time measured on electrocardiogram to improve sensitivity and specificity of exercise tolerance tests

The current exercise tolerance test (ETT) criteria predominantly assess changes in ST-segment deviation (i.e., a systolic component of the cardiac cycle). Because diastolic dysfunction precedes that of systolic dysfunction during myocardial ischemia and most coronary flow is diastolic, the addition of electrocardiographic markers of diastolic time might improve the ETT sensitivity and specificity for detecting significant coronary artery disease. Among consecutive patients who had an ETT and subsequently underwent coronary angiography, we evaluated the diastolic time by assessing the TP and TQ segments and TP/RR and TQ/RR ratios in each ETT stage. Coronary artery disease was defined angiographically as significant (≥70% lumen occlusion), intermediate (>50% but <70% lumen occlusion), or nonsignificant (≤50% lumen occlusion). Of the 48 study patients, hypertension and hyperlipidemia appeared highly prevalent. TP, TQ, TP/RR, and TQ/RR correlated significantly with RR and changed with each ETT stage. Although TP and TQ were not significantly associated with significant coronary artery disease, TP/RR and TQ/RR proved to be, particularly beyond stage 2. When TQ/RR of ≤0.39 and TP/RR of ≤0.13 were used, their individual sensitivities and specificities were reasonably comparable to that of traditional ETT criteria (79% sensitivity and 44% specificity at our institution). Adding TQ/RR of ≤0.39 and/or TP/RR of ≤0.13 to existing ETT criteria improved its sensitivity to 100% and specificity to 86%. In conclusion, the addition of diastolic time indexes of TP/RR and TQ/RR significantly improved the overall ETT diagnostic value above the guideline-oriented, perhaps "traditional," criteria for the diagnosis of myocardial ischemia. Such parameters should be widely investigated further for clinical accuracy and compatibility.

The feasibility of Rubidium-82 positron emission tomography stress testing in low-risk chest pain protocol patients

OBJECTIVE

To evaluate the feasibility of dipyridamole-induced reversible ischemia on myocardial perfusion positron emission tomography (PET) imaging using Rubidium-82 (Rb-82 PET) to predict the presence of acute coronary syndrome (ACS) in emergency department (ED) chest pain patients at low risk who were admitted to an observation unit.

METHODS

Retrospective cross-sectional study of electronic medical records after computerized record retrieval. We matched all ED chest pain visits to a database of all scans read by cardiology between January 1, 2004 and January 1, 2006. A PET scan was performed at the ED physician's discretion after a negative observation unit workup, including serial cardiac biomarkers and ECGs. Data were collected on a standardized abstraction instrument.

RESULTS

There were 7,691 ED visits for chest pain. Among these patients, 1177 had an Rb-82 PET. Fifty four (4.6%) of these patients had an abnormal or probably abnormal scan. Of these, 28 had catheter-proven significant coronary disease, requiring either revascularization or intensive medical management; 22 patients had ACS by clinical assessment but did not undergo catheterization. Four had no coronary artery disease on catheterization.

CONCLUSION

In a low-risk chest pain population, cardiac PET imaging had true-positive cardiac catheterization rates which were comparable to prior studies of SPECT sestimibi imaging and coronary CTA imaging. With the rapid dissemination of PET technology, and superior performance compared to current imaging methods, myocardial perfusion PET is a feasible alternative to traditional provocative testing in an ED observation unit.

Receiver operating characteristic (ROC) curves and the definition of threshold levels to diagnose coronary artery disease on electrocardiographic stress testing. Part I: The use of ROC curves in diagnostic medicine and electrocardiographic markers of ischaemia

A common problem in diagnostic medicine, when performing a diagnostic test, is to obtain an accurate discrimination between 'normal' cases and cases with disease, owing to the overlapping distributions of these populations. In clinical practice, it is exceedingly rare that a chosen cut point will achieve perfect discrimination between normal cases and those with disease, and one has to select the best compromise between sensitivity and specificity by comparing the diagnostic performance of different tests or diagnostic criteria available. Receiver operating characteristic (or receiver operator characteristic, ROC) curves allow systematic and intuitively appealing descriptions of the diagnostic performance of a test and a comparison of the performance of different tests or diagnostic criteria. This review will analyse the basic principles underlying ROC curves and their specific application to the choice of optimal parameters on exercise electrocardiographic (ECG) stress testing. Part I will focus on theoretical description and analysis along with reviewing the common problems related to the diagnosis of myocardial ischaemia by means of exercise ECG stress testing. Part II will be devoted to applying ROC curves to available diagnostic criteria through the analysis of ECG stress test parameters.

Treadmill scores in elderly men

OBJECTIVES

This study seeks to further characterize the role of exercise testing in the elderly for prognosis and diagnosis of coronary artery disease.

BACKGROUND

Recent exercise testing guidelines have recognized that statements regarding the elderly do not have an adequate evidence-based quality because the studies they are based on have limitations in sample size and design. The Duke Treadmill Score has been recommended for risk stratification, but recent evidence has suggested that it does not function in the elderly.

METHODS

The study population consisted of male veterans (1872 patients >or=65 years; 3798 patients <65 years) who underwent routine clinical exercise testing with a mean follow-up of six years. A subset who underwent coronary angiography as clinically indicated (elderly, n = 405; younger, n= 809) were included. The primary outcome for all subjects was cardiovascular mortality with coronary angiographic findings as the outcome in those selected for angiography.

RESULTS

In survival analysis, exercise-induced ST depression was prognostic in both age groups only when cardiovascular death was considered as the end point. Peak metabolic equivalents were the most significant predictor for both age groups only when all-cause death was considered as the end point. New age-specific prognostic scores were developed and found to be predictive for cardiovascular mortality in the elderly. Moreover, in the angiographic subset of the elderly, a specific diagnostic score provided significantly better discrimination than exercise ST measurements alone. For any new score, there is a need for validation in another elderly population.

CONCLUSIONS

The mortality end point affected the choice of prognostic variables. This study demonstrates that exercise test scores can be helpful for the diagnosis and prognosis of coronary disease in the elderly.