Background
There is no angiographically demonstrable obstructive coronary artery
disease (CAD) in a significant minority of patients with myocardial
infarction (MI), particularly women. We sought to determine mechanism(s) of
MI in this setting using multiple imaging techniques.
Methods and Results
Women with MI were enrolled prospectively, prior to angiography if
possible. Women with ≥50% angiographic stenosis or use of
vasospastic agents were excluded. Intravascular ultrasound (IVUS) was
performed during angiography and cardiac magnetic resonance imaging (CMR)
within one week. Fifty women (age 57±13 years) had median peak
troponin 1.60 ng/ml; 11 had ST elevation. Median diameter stenosis of the
worst lesion was 20% by angiography; 15 patients (30%) had
normal angiograms. Plaque disruption was observed in 16/42 patients
(38%) undergoing IVUS. There were abnormal myocardial CMR findings
in 26/44 patients (59%) undergoing CMR: late gadolinium enhancement
(LGE) in 17 and T2 signal hyperintensity indicating edema in 9 additional
patients. The most common LGE pattern was ischemic
(transmural/subendocardial). Non-ischemic LGE patterns
(midmyocardial/subepicardial) were also observed. LGE was infrequent with
plaque disruption but T2 signal hyperintensity was common with plaque
disruption.
Conclusions
Plaque rupture and ulceration are common in women with MI without
angiographically demonstrable obstructive CAD. LGE is also common in this
cohort of women, with an ischemic pattern of injury most evident. Vasospasm
and embolism are possible mechanisms of ischemic LGE without plaque
disruption. IVUS and CMR provide complementary mechanistic insights in
female MI patients without obstructive CAD and may be useful in identifying
potential etiologies and therapies.
Background-Drug-eluting stents (DES) have been in clinical use for nearly a decade; however, the relative short-and long-term efficacy and safety of DES compared with bare-metal stents (BMS) and among the DES types are less well defined. with each other or against BMS for de novo coronary lesions, enrolling at least 100 patients and with follow-up of at least 6 months. Short-term (Յ1 year) and long-term efficacy (target-vessel revascularization, target-lesion revascularization) and safety (death, myocardial infarction, stent thrombosis) outcomes were evaluated and trial-level data pooled by both mixed-treatment comparison and direct comparison analyses. From 76 randomized clinical trials with 117 762 patient-years of follow-up, compared with BMS, each DES reduced long-term target-vessel revascularization (39%-61%), but the magnitude varied by DES type (EESϳSESϳZES-RϾPESϳZESϾBMS), with a Ͼ42% probability that EES had the lowest target-vessel revascularization rate. There was no increase in the risk of any long-term safety outcomes, including stent thrombosis, with any DES (versus BMS). In addition, there was reduction in myocardial infarction (all DES except PES versus BMS) and stent thrombosis (with EES versus BMS: Rate ratio, 0.51; 95% credibility interval, 0.35-0.73). The safest DES appeared to be EES (Ͼ86% probability), with reduction in myocardial infarction and stent thrombosis compared with BMS. Short-term outcomes were similar to long-term outcomes, with SES, ZES-R, and everolimus-eluting stent being the most efficacious and EES being the safest stent. Conclusions-DES are highly efficacious at reducing the risk of target-vessel revascularization without an increase in any safety outcomes, including stent thrombosis. However, among the DES types, there were considerable differences, such that EES, SES, and ZES-R were the most efficacious and EES was the safest stent. (Circulation. 2012;125:2873-2891.)
Background:
Myocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 6-15% of MI and disproportionately affects women. Scientific statements recommend multi-modality imaging in MINOCA to define the underlying cause. We performed coronary optical coherence tomography (OCT) and cardiac magnetic resonance imaging (CMR) to assess mechanisms of MINOCA.
Methods:
In this prospective, multicenter, international, observational study, we enrolled women with a clinical diagnosis of MI. If invasive coronary angiography revealed <50% stenosis in all major arteries, multi-vessel OCT was performed, followed by CMR (cine imaging, late gadolinium enhancement, and T2-weighted imaging and/or T1 mapping). Angiography, OCT, and CMR were evaluated at blinded, independent core laboratories. Culprit lesions identified by OCT were classified as definite or possible. The CMR core laboratory identified ischemia-related and non-ischemic myocardial injury. Imaging results were combined to determine the mechanism of MINOCA, when possible.
Results:
Among 301 women enrolled at 16 sites, 170 were diagnosed with MINOCA, of whom 145 had adequate OCT image quality for analysis; 116 of these underwent CMR. A definite or possible culprit lesion was identified by OCT in 46.2% (67/145) of participants, most commonly plaque rupture, intra-plaque cavity or layered plaque. CMR was abnormal in 74.1% (86/116) of participants. An ischemic pattern of CMR abnormalities (infarction or myocardial edema in a coronary territory) was present in 53.4% of participants undergoing CMR (62/116). A non-ischemic pattern of CMR abnormalities (myocarditis, takotsubo syndrome or non-ischemic cardiomyopathy) was present in 20.7% (24/116). A cause of MINOCA was identified in 84.5% of the women with multi-modality imaging (98/116), higher than with OCT alone (p<0.001) or CMR alone (p=0.001). An ischemic etiology was identified in 63.8% of women with MINOCA (74/116), a non-ischemic etiology was identified in 20.7% (24/116), and no mechanism was identified in 15.5% (18/116).
Conclusions:
Multi-modality imaging with coronary OCT and CMR identified potential mechanisms in 84.5% of women with a diagnosis of MINOCA, three-quarters of which were ischemic and one-quarter of which were non-ischemic, alternate diagnoses to MI. Identification of the etiology of MINOCA is feasible and has the potential to guide medical therapy for secondary prevention.
Clinical Trial Registration:
URL: https://clinicaltrials.gov Unique Identifier: NCT02905357
BARI physicians were able to select PTCA rather than CABG for 65% of registry patients who underwent revascularization without compromising long-term survival either in the overall population or in treated diabetics.
for the AVID InvestigatorsBackground-AVID (Angiography Versus Intravascular ultrasound-Directed stent placement) is a multicenter, randomized controlled trial designed to assess the effect of intravascular ultrasound (IVUS)-directed stent placement on the 12-month rate of target lesion revascularization (TLR). Methods and Results-After elective coronary stent placement and an optimal angiographic result (Ͻ10% stenosis), 800 patients were randomized to Angiography-or IVUS-directed therapy. Blinded IVUS was performed in the Angiography group without further therapy. In the IVUS group, IVUS criteria for optimal stent placement (Ͻ10% area stenosis, apposition, and absence of dissection) were applied. Final minimum stent area was 6.90Ϯ2.43 mm 2 in the Angiography group and 7.55Ϯ2.82 mm 2 in the IVUS group (Pϭ0.001). In the IVUS group, only 37% with inadequate expansion (Ͻ90%) received further therapy. The 12-month TLR rate was 12.0% in the Angiography group and 8.1% in the IVUS group (Pϭ0.08, 95% confidence level [CI], [Ϫ8.3% to 0.5%]). When vessels with a distal reference diameter Ͻ2.5 mm by core laboratory angiography measurement were excluded from analysis, the 12-month TLR rate was 10.1% in the Angiography group and 4.3% in the IVUS group (Pϭ0.01, 95% CI, [Ϫ10.6% to Ϫ1.2%]). With a prestent angiographic stenosis of Ն70%, the TLR rate was lower in the IVUS group compared with the Angiography group (3.1% versus 14.2%; Pϭ0.002; 95% CI, [Ϫ18.4% to Ϫ4.2%]). Conclusions-IVUS-directed bare-metal stent placement results in larger acute stent dimensions without an increase in complications and a significantly lower 12-month TLR rate for vessels Ն2.5 mm by angiography and for vessels with high-grade prestent stenosis. However, for the entire sample analyzed on an intention-to-treat basis, IVUS-directed bare-metal stent placement does not significantly reduce the 12-month TLR rate when compared with stent placement guided by angiography alone. In addition, IVUS evaluation of adequate stent expansion is underutilized by experienced operators. (Circ Cardiovasc Intervent. 2009;2:113-123.)
The Bypass Angioplasty Revascularization Investigation (BARI) trial indicates 5-year cardiac mortality in patients with multivessel disease was significantly greater after initial treatment with PTCA than with CABG. The difference was manifest in diabetic patients on drug therapy. There were no significant differences overall for the composite end point of cardiac mortality or MI between treatment groups or for cardiac mortality in nondiabetic patients regardless of symptoms, left ventricular function, number of diseased vessels, or stenotic proximal left anterior descending artery.
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