Non-obstructive coronary artery disease upon multi-detector computed tomography in patients presenting with acute chest pain--results of an intermediate term follow-up

No correlation between diffuse idiopathic skeletal hyperostosis and coronary artery disease on computed tomography using two different scoring systems

BACKGROUND

An association between diffuse idiopathic skeletal hyperostosis (DISH) and a history of coronary artery disease (CAD) was previously reported.

PURPOSE

To investigate the association between DISH and CAD as assessed using the coronary artery calcification score (CACS) and the CAD-Reporting and Data System (CAD-RADS) score in patients with symptomatic chest pain.

MATERIAL AND METHODS

Consecutive cardiac CT scans performed before and after IV contrast administration were evaluated for CACS (Agatston method), CAD-RADS, and the presence of DISH. The association of DISH with the presence and extent of CACS/CAD-RADS scores was analyzed with and without adjustment for known atherosclerotic risk factors.

RESULTS

The study cohort included 268 individuals (157 men, 111 women; median age = 54 years). DISH was present in 65 (24.3%) individuals. CACS was significantly higher in the DISH group compared to the non-DISH group in the univariate analysis (median CACS DISH = 2, range = 0-80.5 vs. median CACS non-DISH = 0, range = 0-11; P < 0.005) but this association did not persist on multivariate analysis. There was a positive trend toward higher CAD-RADS scores in the DISH group (P = 0.03) but after adjustment for age, male sex, and family history, this tendency was not significant.

CONCLUSION

No independent association was found between the presence of DISH and CACS and CAD-RADS scores. Our findings suggest a more complex and possibly non-causal relationship between coronary artery disease and DISH.

The characteristics of coronary stenosis in 11,267 patients from Southwest China: a retrospective study

The characteristics of coronary stenosis vary among the different countries or areas. 11,267 patients who have undergone coronary angiography (CAG) from three Southwest China hospitals were investigated. Patient characteristics, coronary stenosis and stent-implant information were recorded and analyzed according to two criteria: "visible stenosis" and "≥ 50% stenosis". The patients who have undergone CAG increased year by year, with patients from 60 to 69 years-old taking the highest ratio (34.69%). Based on the "≥ 50% stenosis" criteria, the stenotic frequency was 40.54% for Southwest China patients getting CAG. Only 8.14% patients suffered ≥ 3 stenotic vessels, while 11.58 and 20.82% patients had 2 or 1 stenotic vessel, respectively. However, when using the "visible stenosis" criteria, the stenotic frequency increased to 64.68%. The prevalence of stenosis increased with age based on the "visible stenosis" criteria. There were more male patients with stenosis than female except patients over 80 years old. The stenosis affected almost all main coronary arteries and their branches, with the most affected artery being the left anterior descending artery. There were 3246 cases (28.8%) implanted with 5423 stents with a concurrent age-dependent increasing tendency for stent-implant frequency and average implanted stent number. The numbers of patients who have undergone CAG and suffered from CVD increased rapidly. In these patients, positive rate of CAG was 64.67%, which increased to 72.2% in patients over 60-years old. The incidence of ≥ 75% stenosis and multiple stenosis increased with age, however it should be noticed there were 18.93% for ≥ 75% stenosis and 19.52% for multiple stenosis in patients under 40 years old.

Prevalence and Prognosis of Nonobstructive Coronary Artery Disease in Patients Undergoing Coronary Angiography or Coronary Computed Tomography Angiography: A Meta-Analysis

OBJECTIVE

To evaluate the prevalence, clinical characteristics, and risk of cardiac events in patients with nonobstructive coronary artery disease (CAD).

PATIENTS AND METHODS

We searched PubMed, EMBASE, and the Cochrane Library from January 1, 1990, to November 31, 2015. Studies were included if they reported prevalence or prognosis of patients with nonobstructive CAD (≤50% stenosis) among patients with known or suspected CAD. Patients with nonobstructive CAD were further grouped as those with no angiographic CAD (0% or ≤20%) and those with mild CAD (>0% or >20% to ≤50%). Data were pooled using random effects modeling, and annualized event rates were assessed.

RESULTS

Fifty-four studies with 1,395,190 participants were included. The prevalence of patients with nonobstructive CAD was 67% (95% CI, 63%-71%) among patients with stable angina and 13% (95% CI, 11%-16%) among patients with non-ST-segment elevation acute coronary syndrome. The prevalence varied depending on sex, clinical setting, and risk profile of the population investigated. The risk of hard cardiac events (cardiac death or myocardial infarction) in patients with mild CAD was lower than that in patients with obstructive CAD (risk ratio, 0.28; 95% CI, 0.20-0.38) but higher than that in those with no angiographic CAD (risk ratio, 1.85; 95% CI, 1.52-2.26). The annualized event rates of hard cardiac events in patients with no angiographic CAD, mild CAD, and obstructive CAD were 0.3% (95% CI, 0.1%-0.4%), 0.7% (95% CI, 0.5%-1.0%), and 2.7% (95% CI, 1.7%-3.7%), respectively, among patients with stable angina and 1.2% (95% CI, 0.02%-2.3%), 4.1% (95% CI, 3.3%-4.9%), and 17.0% (95% CI, 8.4%-25.7%) among patients with non-ST-segment elevation acute coronary syndrome. The correlation between CAD severity and prognosis is consistent regardless of clinical presentation of all-cause death, myocardial infarction, total cardiovascular events, and revascularization.

CONCLUSION

Nonobstructive CAD is associated with a favorable prognosis compared with obstructive CAD, but it is not benign. The high prevalence and impaired prognosis of this population warrants further efforts to improve the risk stratification and management of patients with nonobstructive CAD.

Nonobstructive coronary artery disease and risk of myocardial infarction

IMPORTANCE

Little is known about cardiac adverse events among patients with nonobstructive coronary artery disease (CAD).

OBJECTIVE

To compare myocardial infarction (MI) and mortality rates between patients with nonobstructive CAD, obstructive CAD, and no apparent CAD in a national cohort.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of all US veterans undergoing elective coronary angiography for CAD between October 2007 and September 2012 in the Veterans Affairs health care system. Patients with prior CAD events were excluded.

EXPOSURES

Angiographic CAD extent, defined by degree (no apparent CAD: no stenosis >20%; nonobstructive CAD: ≥1 stenosis ≥20% but no stenosis ≥70%; obstructive CAD: any stenosis ≥70% or left main [LM] stenosis ≥50%) and distribution (1, 2, or 3 vessel).

MAIN OUTCOMES AND MEASURES

The primary outcome was 1-year hospitalization for nonfatal MI after the index angiography. Secondary outcomes included 1-year all-cause mortality and combined 1-year MI and mortality.

RESULTS

Among 37,674 patients, 8384 patients (22.3%) had nonobstructive CAD and 20,899 patients (55.4%) had obstructive CAD. Within 1 year, 845 patients died and 385 were rehospitalized for MI. Among patients with no apparent CAD, the 1-year MI rate was 0.11% (n = 8, 95% CI, 0.10%-0.20%) and increased progressively by 1-vessel nonobstructive CAD, 0.24% (n = 10, 95% CI, 0.10%-0.40%); 2-vessel nonobstructive CAD, 0.56% (n = 13, 95% CI, 0.30%-1.00%); 3-vessel nonobstructive CAD, 0.59% (n = 6, 95% CI, 0.30%-1.30%); 1-vessel obstructive CAD, 1.18% (n = 101, 95% CI, 1.00%-1.40%); 2-vessel obstructive CAD, 2.18% (n = 110, 95% CI, 1.80%-2.60%); and 3-vessel or LM obstructive CAD, 2.47% (n = 137, 95% CI, 2.10%-2.90%). After adjustment, 1-year MI rates increased with increasing CAD extent. Relative to patients with no apparent CAD, patients with 1-vessel nonobstructive CAD had a hazard ratio (HR) for 1-year MI of 2.0 (95% CI, 0.8-5.1); 2-vessel nonobstructive HR, 4.6 (95% CI, 2.0-10.5); 3-vessel nonobstructive HR, 4.5 (95% CI, 1.6-12.5); 1-vessel obstructive HR, 9.0 (95% CI, 4.2-19.0); 2-vessel obstructive HR, 16.5 (95% CI, 8.1-33.7); and 3-vessel or LM obstructive HR, 19.5 (95% CI, 9.9-38.2). One-year mortality rates were associated with increasing CAD extent, ranging from 1.38% among patients without apparent CAD to 4.30% with 3-vessel or LM obstructive CAD. After risk adjustment, there was no significant association between 1- or 2-vessel nonobstructive CAD and mortality, but there were significant associations with mortality for 3-vessel nonobstructive CAD (HR, 1.6; 95% CI, 1.1-2.5), 1-vessel obstructive CAD (HR, 1.9; 95% CI, 1.4-2.6), 2-vessel obstructive CAD (HR, 2.8; 95% CI, 2.1-3.7), and 3-vessel or LM obstructive CAD (HR, 3.4; 95% CI, 2.6-4.4). Similar associations were noted with the combined outcome.

CONCLUSIONS AND RELEVANCE

In this cohort of patients undergoing elective coronary angiography, nonobstructive CAD, compared with no apparent CAD, was associated with a significantly greater 1-year risk of MI and all-cause mortality. These findings suggest clinical importance of nonobstructive CAD and warrant further investigation of interventions to improve outcomes among these patients.

Prognosis of Troponin-Positive Patients with Non-Obstructive Coronary Artery Disease

Introduction

Troponin elevation is an independent risk factor for mortality, but the prognosis of patients with troponin elevation and non-obstructive coronary artery disease (CAD) is unknown. Recent data have suggested an increased risk of mortality. This study was performed to further investigate the outcomes of troponin-positive patients with obstructive and non-obstructive CAD.

Methods

A retrospective cohort analysis was performed of all patients with raised troponin presenting to Kettering General Hospital (January 2010 to December 2011, n = 1,351). The patients who had angiograms were stratified anatomically into obstructive CAD and non-obstructive CAD (≤50% stenosis). The obstructive CAD group (O-CAD) was sub-analyzed by management strategy: emergency re-vascularization (<12 h), urgent, delayed, and medically managed. Patients with non-obstructive CAD were grouped by the cause of the raised troponin if this could be identified (NO-CAD-I) or cause remained unidentified (NO-CAD-U). The major adverse cardiac and cerebrovascular event (MACCE) and mortality rates were calculated at 30 days and 1-year follow-up.

Results

There was a preponderance of hypertension and severe renal impairment in the non-obstructive CAD group. The patients with NO-CAD-U were a low-risk group (MACCE at 1-year follow-up = 0). The remaining NO-CAD-I group had a similar risk to the O-CAD group for MACCE and mortality at 30 days and 1-year follow-up. In fact, at 1-year follow-up, the NO-CAD-I patients when compared with the subgroups of O-CAD, had higher MACCE rates and mortality compared with the emergency re-vascularized group [MACCE: relative risk (RR) (95% CI) = 2.27 (1.29–3.40), P = 0.0047; mortality: RR (95% CI) = 2.08 (1.10–3.93), P = 0.024]. This was driven by higher risk non-cardiac death [RR (95% CI) = 4.10 (1.53–10.99), P = 0.005].

Conclusion

Patients with identified cause for raised troponin and non-obstructive CAD are at equivalent risk of MACCE and mortality at 30 days and 1-year follow-up compared to those with obstructive CAD.

Electronic supplementary material

The online version of this article (doi:10.1007/s40119-014-0027-6) contains supplementary material, which is available to authorized users.

The year 2012 in the European Heart Journal-Cardiovascular Imaging: Part I

The new multi-modality cardiovascular imaging journal, European Heart Journal - Cardiovascular Imaging, was started in 2012. During its first year, the new Journal has published an impressive collection of cardiovascular studies utilizing all cardiovascular imaging modalities. We will summarize the most important studies from its first year in two articles. The present 'Part I' of the review will focus on studies in myocardial function, myocardial ischaemia, and emerging techniques in cardiovascular imaging.

Prognostic implications of nonobstructive coronary artery disease in patients undergoing coronary computed tomographic angiography for acute chest pain

Coronary computed tomographic angiography can detect nonobstructive atherosclerotic lesions that would not otherwise have been detected with functional cardiac imaging. Currently, limited data exist regarding the clinical significance of these lesions in patients with acute chest pain. The aim of our study was to examine the prognostic significance of these nonobstructive findings in a patient population presenting with acute chest pain. We evaluated 959 consecutive patients who underwent coronary computed tomographic angiography for investigation of acute chest pain. The patients were classified as having normal (n = 545), nonobstructive coronary artery disease (CAD; defined as any narrowing <50% diameter stenosis; n = 312), or obstructive CAD (narrowing of ≥50% diameter stenosis; n = 65). Follow-up data for a minimum of 12 months (mean 27 ± 11) was obtained for any major adverse coronary events consisting of death, nonfatal acute coronary syndrome, and coronary revascularization. Compared to patients with normal coronary arteries, those with nonobstructive CAD were older and had a greater prevalence of CAD risk factors. The incidence of major adverse coronary events was equally low among both these groups (0.6% vs 1.3%, for the normal and nonobstructive groups, respectively, p = 0.2). In conclusion, patients with either nonobstructive CAD or normal findings, as evaluated by coronary computed tomographic angiography, for acute chest pain during an intermediate-term follow-up period had equally benign clinical outcomes.