Ahmed Mashaly

Percutaneous coronary intervention versus optimal medical therapy for chronic total coronary occlusion with well-developed collaterals

Background The impact of percutaneous coronary intervention (PCI) on chronic total occlusion in patients with well‐developed collaterals is not clear. Methods and Results A total of 640 chronic total occlusion patients with collateral flow grade ≥2 were divided into 2 groups; chronic total occlusion patients either treated with PCI (the PCI group; n=305) or optimal medical therapy (the optimal medical therapy group; n=335). To adjust for potential confounders, a propensity score matching analysis was performed. Major clinical outcomes were compared between the 2 groups up to 5 years. In the entire population, the PCI group had a lower hazard of myocardial infarction (hazard ratio [HR], 0.177; P=0.039; 95% confidence interval [CI], 0.03–0.91) and the composite of total death or myocardial infarction (HR, 0.298; P=0.017; 95% CI, 0.11–0.80); however, it showed higher hazard of target lesion revascularization (HR, 3.942; P=0.003; 95% CI, 1.58–9.81) and target vessel revascularization (HR, 4.218; P=0.001; 95% CI, 1.85–9.60). After propensity score matching, a total of 158 matched pairs were generated. Although the PCI group showed a higher hazard of target lesion revascularization (HR, 2.868; P=0.027; 95% CI, 1.13–7.31) and target vessel revascularization (HR=2.62; P=0.022; 95% CI, 1.15–5.97), it still exhibited a lower incidence of the composite of total death or myocardial infarction (HR, 0.263; P=0.017; 95% CI, 0.087–0.790). The mean ejection fraction was improved from 47.8% to 51.6% (P<0.001) after PCI. Conclusions In our study, successful revascularization by PCI for chronic total occlusion lesions with well‐developed collaterals was associated with lower incidence of death and myocardial infarction, improved left ventricular function, but increased repeat revascularization rate.

Angiotensin-converting enzyme inhibitors versus angiotensin II receptor blockers in acute ST-segment elevation myocardial infarction patients with diabetes mellitus undergoing percutaneous coronary intervention

BACKGROUND Diabetes Mellitus (DM) is an important factor of adverse cardiovascular events in acute ST-segment elevation myocardial infarction (STEMI) patients. Renin-angiotensin-aldosterone system (RAAS) inhibitors is associated with improved clinical outcomes, however, there are limited data comparing the effectiveness of two different RAAS inhibitors in STEMI patients with DM undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES). METHODS A total of 3811 eligible STEMI patients with DM were enrolled in Korea Acute Myocardial Infarction Registry (KAMIR). They were stratified into two groups: Angiotensin converting enzyme inhibitors (ACEI) group (n=2691) and angiotensin receptor blockers (ARB) group (n=1120). To adjust baseline confounding factors, we performed propensity score matching (PSM) analysis and evaluated individual and composite major clinical outcomes between the two groups up to 2years. RESULTS After PSM, a total of 1049 well-matched pairs were generated. Baseline clinical, angiographic and procedural characteristics were well-balanced between the two groups. The incidence of death, recurrent myocardial infarction (MI), revascularization and major adverse cardiac events (MACE) were not significantly different between the two groups up to 2years, CONCLUSION: In the present study, ACEI and ARB showed comparable effectiveness and safety on individual and composite clinical outcomes in STEMI patients with DM who underwent successful PCI with DES at least up to 2years.

Three-year follow-up of patients with acetylcholine-induced coronary artery spasm combined with insignificant coronary stenosis

BACKGROUND Coronary artery spasm (CAS) and significant coronary stenosis are known to be major causes of myocardial ischemia. However, their association and the impact of insignificant coronary stenosis (ICS) on long-term clinical outcomes of CAS patients are largely unknown. METHODS A total of 2797 patients without significant coronary artery disease (CAD) who underwent the acetylcholine (ACH) provocation test between November 2004 and October 2010 were enrolled. Significant CAS was defined as having ≥70% of temporary narrowing by ACH test and ICS as having <70% of fixed stenosis on angiography. Patients were divided into two groups: ICS group (n=764) and non-ICS group (n=845). To adjust potential confounders, a propensity score matching (PSM) analysis was performed using the logistic regression model. Primary endpoint was the composite of total death, myocardial infraction (MI), de novo percutaneous coronary intervention (PCI), and cerebrovascular accidents (CVA). Secondary endpoint was the incidence of recurrent angina requiring repeat coronary angiography (CAG) at 3years. RESULTS After PSM analysis, two well-balanced groups (548 pairs, total=1096) were generated. The baseline clinical characteristics were similar between the two groups. During the ACH test, compared with the non-ICS group, the ICS group had smaller spastic narrowing diameter (0.69±0.35 vs. 0.73±0.37, P=0.039) and incidence of ST-segment depression (4.0% vs. 0.9%, P=0.001). The incidence of primary and secondary endpoints was similar between the two groups up to 3years. CONCLUSIONS Although, the ICS group was expected to have more adverse long-term clinical outcomes, it was not associated with the increased incidence of major adverse clinical outcomes compared with the non-ICS group up to 3years. Longer term follow-up studies are needed.

Hyperuricaemia and development of type 2 diabetes mellitus in Asian population

Recently, meta‐analysis studies reported that hyperuricaemia is associated with higher incidence of type 2 diabetes mellitus (T2DM), however, there are limited data on the Asian population. The aim of this observational study is to estimate the long‐term impact of hyperuricaemia on the new‐onset T2DM and cardiovascular events. This study is based on a single‐centre, all‐comers, and large retrospective cohort. Subjects that visited from January 2004 to February 2014 were enrolled using the electronic database of Korea University Guro Hospital. A total of 10 505 patients without a history of T2DM were analyzed for uric acid, fasting glucose and haemoglobin (Hb) A1c level. Inclusion criteria included both Hb A1c <5.7% and fasting glucose level <100 mg/dL without T2DM. Hyperuricaemia was defined as a uric acid level ≥7.0 mg/dL in men, and ≥6.5 mg/dL in women. To adjust baseline confounders, a propensity score matching (PSM) analysis was performed. The impact of hyperuricaemia on the new‐onset T2DM and cardiovascular events were compared with the non‐hyperuricaemia during the 5‐year clinical follow‐up. After PSM, baseline characteristics of both groups were balanced. In a 5‐year follow‐up, the hyperuricaemia itself was a strong independent predictor of the incidence of new‐onset T2DM (HR, 1.78; 95% CI, 1.12 to 2.8). Hyperuricaemia was a strong independent predictor of new‐onset T2DM, which suggests a substantial implication for a correlation between uric acid concentration and insulin resistance (or insulin sensitivity). Also, hyperuricaemia is substantially implicated in cardiovascular risks and the further long‐term cardiovascular events in the crude population, but it is not an independent predictor of long‐term cardiovascular mortality in the matched population.

Selective ß1-blockers are not associated with new-onset diabetes mellitus in hypertensive patients

Background: Although ß-blockers are known to increase new-onset diabetes mellitus (DM), previous evidence have been controversial. It has been suggested that newer vasodilatory ß-blockers yield better glycemic control than older nonselective agents. The aim of this study was to evaluate the diabetogenicity of currently used newer ß-blockers based on ß1 receptor selectivity in a series of Asian population. Methods: We investigated a total of 65,686 hypertensive patients without DM from 2004 to 2014. Patients with hemoglobin (Hb) A1c ⩽6.0%, fasting blood glucose ⩽110 mg/dL, and no history of diabetes or diabetic treatment were enrolled for analysis. Patients were divided into the ß-blockers group and non-ß-blockers group. Propensity score matching (PSM) analysis using a logistic regression model was performed to adjust for potential confounders. The primary end point was the cumulative incidence of new-onset DM, defined as a fasting blood glucose ≥126 mg/dL or HbA1c ≥6.5%, and major adverse cardiac and cerebral events (MACCE), defined as a composite of total death, nonfatal myocardial infarction, and cerebrovascular accidents. We investigated predictors of new-onset DM and MACCE based on 2 models, including clinical risk factors and co-medications, respectively. Results: Mean follow-up duration was 30.91 ± 23.14 months in the entire group before adjustment. The ß-blockers group had a significantly higher incidence of new-onset DM and MACCE than the non-ß-blockers group. After PSM, analysis of a total of 2284 patients (1142 pairs, C-statistic = 0.752) showed no difference between the 2 groups in new-onset DM or MACCE. In multivariate analysis after PSM, baseline HbA1c, stroke, heart failure, nonselective ß-blockers, and age were independent predictors of new-onset DM. Selective ß1-blockers did not increase new-onset DM after adjustment for other antihypertensive medication and statins. Conclusions: In the era of newer ß-blockers, selective ß1-blockers were not associated with new-onset DM. More evidence is needed to verify this relationship and the underlying mechanisms.

The impact of prediabetes on two-year clinical outcomes in patients undergoing elective percutaneous coronary intervention

Purpose Prediabetes is an independent risk factor for cardiovascular disease. However, data on the long term adverse clinical outcomes of prediabetic patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) are scarce. Materials and Methods The study population comprised 674 consecutive non-diabetic patients who underwent elective PCI between April 2007 and November 2010. Prediabetes was defined as hemoglobin A1c (HbA1c) of 5.7% to 6.4%. Two-year cumulative clinical outcomes of prediabetic patients (HbA1c of 5.7% to 6.4%, n=242) were compared with those of a normoglycemic group (<5.7%, n=432). Results Baseline clinical and angiographic characteristics were similar between the two groups, except for higher glucose levels (104.8±51.27 mg/dL vs. 131.0±47.22 mg/dL, p<0.001) on admission in the prediabetes group. There was no significant difference between the two groups in coronary angiographic parameters, except for a higher incidence of diffuse long lesion in the prediabetes group. For prediabetic patients, trends toward higher incidences of binary restenosis (15.6% vs. 9.8 %, p=0.066) and late loss (0.71±0.70 mm vs. 0.59±0.62 mm, p=0.076) were noted. During the 24 months of follow up, the incidence of mortality in prediabetic patients was higher than that in normoglycemic patients (5.5% vs. 1.5%, p=0.007). Conclusion In our study, a higher death rate and a trend toward a higher incidence of restenosis in patients with prediabetes up to 2 years, compared to those in normoglycemic patients, undergoing elective PCI with contemporary DESs.

Five-year outcomes of successful percutaneous coronary intervention with drug-eluting stents versus medical therapy for chronic total occlusions

Purpose Many recent studies have reported that successful percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) for chronic total occlusion (CTO) has more beneficial effects than failed CTO-PCI; however, there are only limited data available from comparisons of successful CTO-PCI with medical therapy (MT) in the Korean population. Materials and Methods A total of 840 consecutive CTO patients who underwent diagnostic coronary angiography, receiving either PCI with DESs or MT, were enrolled. Patients were divided into two groups according to the treatment assigned. To adjust for potential confounders, propensity score matching (PSM) analysis was performed using logistic regression. Individual major clinical outcomes and major adverse cardiac events, a composite of total death, myocardial infarction (MI), stroke, and revascularization, were compared between the two groups up to 5 years. Results After PSM, two propensity-matched groups (265 pairs, n=530) were generated, and the baseline characteristics were balanced. Although the PCI group showed a higher incidence of target lesion and vessel revascularization on CTO, the incidence of MI tended to be lower [hazard ratio (HR): 0.339, 95% confidence interval (CI): 0.110 to 1.043, p=0.059] and the composite of total death or MI was lower (HR: 0.454, 95% CI: 0.224 to 0.919, p=0.028), compared with the MT group up to 5 years. Conclusion In this study, successful CTO PCI with DESs was associated with a higher risk of repeat PCI for the target vessel, but showed a reduced incidence of death or MI.

Routine angiographic follow-up versus clinical follow-up in patients with diabetes following percutaneous coronary intervention with drug-eluting stents in Korean population

AIMS The usefulness of routine angiographic follow-up (RAF) and clinical follow-up (CF) after percutaneous coronary intervention (PCI) in patients with diabetes is not well understood. We compare 3-year clinical outcomes of RAF and CF in diabetic patients underwent PCI with drug-eluting stents (DES). METHODS A total of 843 patients with diabetes who underwent PCI with DES were enrolled. RAF was performed at 6-9 months after PCI (n = 426). Rest of patients were medically managed and clinically followed (n = 417); symptom-driven events were captured. After propensity score matched analysis, 2 propensity-matched groups (262 pairs, n = 524, C-statistic = 0.750) were generated. The primary endpoint was major adverse cardiac events (MACE), the composite of total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-target vessel revascularization (Non-TVR). RESULTS During the 3-year follow-up period, the cumulative incidence of target lesion revascularization [TLR: hazard ratio (HR), 4.07; 95% confidence interval (CI), 1.18-9.34; p = 0.001], target vessel revascularization (TVR: HR, 4.02; 95% CI, 1.93-8.40; p < 0.001), non-TVR (HR, 4.92; 95% CI, 1.68-14.4; p = 0.004) and major adverse cardiac events (MACE: HR, 2.53; 95% CI, 1.60-4.01, p < 0.001) were significantly higher in the RAF group. However, the incidence of total death, non-fatal MI were similar between the two groups. CONCLUSIONS RAF following index PCI with DES in patients with diabetes was associated with increased incidence of revascularization and MACE without changes of death or re-infarction rates and increased TLR and TVR rates in both first- and second-generation DES.

The association of chronic air pollutants with coronary artery spasm, vasospastic angina, and endothelial dysfunction

Background We evaluated the effect of chronic exposure to air pollutants (APs) on coronary endothelial function and significant coronary artery spasm (CAS) as assessed by intracoronary acetylcholine (ACH) provocation test. Patients and methods A total of 6430 patients with typical or atypical chest pain who underwent intracoronary ACH provocation test were enrolled. We obtained data on APs from the Korean National Institute of Environmental Research (http://www.nier.go.kr/). APs are largely divided into two types: particulate matter with aerodynamic diameter of less than or equal to 10 µm in size (PM10) and gaseous pollutants such as nitrogen dioxide, sulfur dioxide, carbon monoxide, and ozone. The primary endpoint is the incidence of significant CAS and its associated parameters during ACH provocation test. Results The incidence of CAS was positively correlated with an exposure duration of PM10, whereas nitrogen dioxide, sulfur dioxide, carbon monoxide, and ozone were shown to be unrelated to CAS. During the ACH provocation test, as PM10 increased, the frequency of CAS was increased, and the incidence of transient ST-segment elevation was also increased. There was a trend toward higher incidence of spontaneous spasm as PM10 increased. The mean exposure level of PM10 was 51.3±25.4 µg/m3. The CAS risk increased by 4% when the level of PM10 increased by 20 µg/m3 by an adjusted Cox regression analysis. Conclusion CAS incidence is closely related to exposure to PMs but not to gaseous pollutants. Particularly, higher exposure concentrations and longer exposure duration of PM10 increased the risk of CAS. These important findings provide a plausible mechanism that links air pollution to vasospastic angina and provide new insights into environmental factors.

The impact of myocardial bridge on coronary artery spasm and long-term clinical outcomes in patients without significant atherosclerotic stenosis

BACKGROUND AND AIMS Myocardial bridge (MB) and coronary artery spasm (CAS) can induce a sustained chest pain, acute coronary syndrome (ACS) and even sudden cardiac death. The aim of this study is to evaluate the relationship between MB and CAS and its impact on long-term clinical outcomes. METHODS A total of 812 patients with MB without significant coronary artery disease (CAD), who underwent acetylcholine (ACH) provocation test, were enrolled. Significant CAS was defined as ≥70% temporary narrowing by ACH test, and MB was defined as the characteristic phasic systolic compression of the coronary artery with a decrease of more than 30% in diameter on the angiogram after intracoronary nitroglycerin infusion. To adjust baseline confounders, logistic regression analysis was performed. The primary endpoint was incidence of CAS, and secondary endpoints were major adverse cardiac events (MACE) and recurrent angina requiring repeat coronary angiography (CAG) at 5 years. RESULTS MB is closely implicated in a high incidence of CAS, spontaneous spasm, ischemic ECG change and chest pain during ACH provocation test. In addition, MB of various severity and reference vessel size was substantially implicated in CAS incidence, and severe MB was a strong risk factor of CAS. MB patients with CAS were shown to have a higher rate of recurrent angina compared with MB patients without CAS, up to a 5-year follow-up. However, there were no differences regarding the incidence of MACE. CONCLUSIONS Severe MB was associated with high incidence of CAS, and MB patients with CAS were likely to have a higher incidence of recurrent angina. Intensive medical therapy and close clinical follow-up are needed for better clinical outcomes in MB patients with CAS.