Angiographic evaluation of flow distribution in sequential and composite arterial grafts for three vessel disease.

OBJECTIVES: We sought to delineate the effects of the severity of target lesions and their combinations on the occurrence of competitive flow, especially in the composite Y-graft and to establish an optimal strategy for graft arrangement and patient selection. METHODS: We reviewed early and late angiograms of 2514 bypass grafts in 601 patients, who underwent off-pump coronary revascularization to three-vessel vascular regions using the internal thoracic artery (ITA) and radial artery (RA) without aortic manipulation. As a standard technique, the left anterior descending artery (LAD) was bypassed with the in situ ITA, and the left circumflex and right coronary arteries (RCA) were bypassed with the composite RA. Bypass flow was graded as antegrade, competitive or no flow. RESULTS: The early patency rate was 98.1% (2466/2514), while competitive flow was detected in 6.4% (162/2514). For the LAD, the individual and sequential in situ ITA provided lower incidence of competitive flow than the composite graft (0.3% (1/298) versus 7.6% (23/303), P < 0.0001). Regarding the RA to non-LAD bypass, 86.3% (113/131) of competitive flow occurred at the distal end of the I- or Y-graft, and the cumulative patency rate was significantly lower than that of sequential proximal anastomosis (80.1 versus 56.6% at 5 years, P < 0.0001). The number of sequential anastomoses did not affect the cumulative patency rate (P = 0.09). For the composite Y-graft to three-vessel regions, the rate of antegrade flow in patients with 76-100% stenosis in both the LAD and the RCA was 95.7% (178/186), which was significantly higher than that of 78.1% (100/128) in patients with 76-100% stenosis in the LAD and 51-75% stenosis in RCA (P < 0.0001). CONCLUSIONS: Sequential and composite grafting was considered reliable, exclusively in appropriately selected situations. To secure entire patency of the Y-graft to three-vessel regions, balanced bypass flow toward LAD and RCA would be crucial.

Effect of pretreatment with pioglitazone on reperfusion injury in diabetic patients with acute myocardial infarction.

BACKGROUND: Pioglitazone (PIO) is a new class of anti-diabetic agent with an anti-inflammatory effect. In the experimental studies, pretreatment with PIO before ischemia/reperfusion reduced ischemia-reperfusion injury and myocardial infarct size. However, the clinical efficacy of this therapy in patients with acute myocardial infarction (AMI) remains unknown. METHODS AND RESULTS: Three hundred and nineteen diabetic patients with ST-segment elevation AMI, treated with bare metal stent within 24h from the onset of AMI were examined. Myocardial blush grade, ST-segment resolution, peak creatine kinase (CK) level, and left ventricular ejection fraction (LVEF) were compared between PIO group (pretreatment with PIO [+]; n=26) and non-PIO group (pretreatment with PIO [-]; n=293). The PIO group showed a significantly higher incidence of blush score ≥ 2 and complete ST-segment resolution (blush score ≥ 2; 38% vs. 71%, P=0.04, ST-segment resolution; 44% vs. 71%, P=0.04). Besides, slow flow/no-reflow phenomenon and reperfusion arrhythmia did not occur in this group. Better improvement of LVEF and lower peak CK level was observed in this group, although these were not statistically significant (LVEF 48% vs. 41%, P=0.10, peak CK level 2,041 vs. 3,207, P=0.06). CONCLUSIONS: Pretreatment with PIO in diabetic patients with AMI resulted in better myocardial perfusion with less reperfusion injury.

Efficacy of paclitaxel-eluting stent in patients with impaired glucose tolerance--comparison with sirolimus-eluting stent.

BACKGROUND: Experimental and clinical studies have shown that paclitaxel-eluting stent (PES) attenuates the effect of diabetes on re-stenosis after percutaneous coronary intervention. Although impaired glucose tolerance (IGT) is a pre-diabetic phase characterized as post-prandial hyperglycemia and hyperinsulinemia, the efficacy of PES in these pre-diabetic patients remains unknown. The purpose of the present study was therefore to compare the efficacy of PES in IGT patients with that of sirolimus-eluting stent (SES). METHODS AND RESULTS: A total of 370 IGT patients with coronary artery disease were examined (SES, n=229; PES, n=141). The incidence of major adverse cardiovascular events (MACE; all-cause death, non-fatal myocardial infarction or repeat revascularization) was compared between the 2 groups. The PES group had lower body mass index, total cholesterol and low-density lipoprotein cholesterol levels and higher prevalence of previous myocardial infarction than the SES group. The incidence of repeat revascularization in the PES group was similar to that in the SES group (22% vs. 19%, P=0.71). The incidence of hard cardiac events such as all-cause death and non-fatal myocardial infarction were also similar between the 2 groups. Finally, there were no significant differences in MACE between the SES and PES groups (23% vs. 21%, P=0.76). CONCLUSIONS: In patients with IGT, the efficacy of PES was similar to that of SES, and any advantage of PES over SES was not observed in these pre-diabetic patients.

A 10-year angiographic follow-up of competitive flow in sequential and composite arterial grafts.

OBJECTIVE: Physiological reaction to competitive flow is considered as the primary mechanism of arterial graft occlusion. Reopening of graft lumen had been also reported, but details remain unknown. We sought to delineate the effect of management of the moderately stenotic targets on the occurrence of competitive flow and clinical results. METHODS: Clinical records and angiograms of 3263 bypass grafts in 852 patients, who underwent off-pump coronary revascularization using the internal thoracic artery (ITA) and radial artery without aortic manipulation since 2000, were examined. Dominant flow direction was graded as antegrade, competitive, and no flow (occlusion). Late angiography was performed in 157 patients with 561 bypass grafts for clinical reasons. The follow-up period was 55.5 ± 31.1 months. RESULTS: The early graft patency rate was 98.0% (3197/3263). The rate of antegrade flow was 91.5% (2986/3263), while competitive flow was detected in 6.5% (211/3263). The actuarial patency rates of bypass grafts with antegrade flow were significantly higher than those with competitive flow (87.9% at 5 years and 71.3% at 8 years, vs 25.8% at 5 years and 9.2% at 8 years, p<0.0001). In the univariate and multivariate analyses for 852 patients, territory of right coronary artery (odds ratio (OR)=2.20, p=0.0002), composite radial artery (OR=1.90, p=0.03), and the distal end of the graft (OR=2.90, p=0.0003), were identified as the significant predictors of competitive flow from the target with 51-75% stenosis. Individual grafting inversely correlated with occurrence of competitive flow (OR=0.48, p=0.04). Reopening of the graft lumen associated with progression of native stenosis was not observed in these patients. CONCLUSIONS: Competitive flow can be efficiently avoided by appropriate graft arrangement and patients' selection. Selection of the target of the graft end would be crucial to achieve antegrade bypass flow and long-term patency of entire sequential bypass grafts. For the composite graft, functional recovery of the occluded graft would be extremely rare.

Determinants for successful sequential radial artery grafting to the left circumflex and right coronary arteries.

The aim of this retrospective observational study was to delineate determinants for antegrade flow and entire patency of the sequential radial artery graft (RAG) in the left circumflex artery (LCX) and right coronary artery (RCA). Angiograms of 432 RAGs, which were sequentially anastomosed to the LCX and RCA, and were proximally anastomosed with the in-situ internal thoracic artery as the composite I- or Y-graft, were studied. The mean targets of RAG were 2.83±0.79. We examined effects of characteristics of RAG and the targets, such as native coronary stenosis and their combinations, on competitive flow and occlusion. Of 432 RAGs, 413 (95.6%) were patent to all targets, while 331 (76.6%) provided antegrade flow to all targets in sequential anastomoses. By the univariate and multivariate analyses, 51-75% stenosis of the most distal target was identified as the significant predictor of competitive flow or occlusion (OR=8.59, P<0.0001). The cumulative graft patency rate of RAGs with 76-100% stenosis of the most distal target at 40 months was 88.6%, whereas that of RAGs with 51-75% stenosis of the most distal target was 59.1% (P<0.0001). In sequential RAG, severity of stenosis in the most distal target had the significant impact on prevention of competitive flow and long-term patency to all targets.

A rare connection by newly formed conduit vessels between the left internal mammalian artery and radial artery bypass grafts after failure of grafts.

Neovascularization such as formation of collateral vessels following total occlusion of native coronary artery is common in coronary artery disease. This is a case report of a very rare connection by newly formed conduit vessels between the left internal mammalian artery and the radial artery establishing bypass, which occurred after failure of bypass grafts.

Post-load hyperglycemia as an important predictor of long-term adverse cardiac events after acute myocardial infarction: a scientific study.

BACKGROUND: Diabetes mellitus (DM) and impaired glucose tolerance (IGT) are risk factors for acute myocardial infarction (AMI). However, it is unknown whether hyperglycemic state is associated with increased major adverse cardiovascular events (MACE) after AMI. In this study, we evaluated the relationship between glucometabolic status and MACE in patients after AMI, and determined the critical level of 2 h post-load plasma glucose that may be used to predict MACE. METHODS: AMI patients (n = 422) were divided into 4 groups as follows: normal glucose tolerance (NGT) group, IGT group, newly diagnosed DM (NDM) group, and previously known DM (PDM) group. MACE of the 4 groups were compared for 2 years from AMI onset. RESULTS: The NDM group had a significantly higher event rate than the IGT and NGT groups and had a similar event rate curve to PDM group. The logistic models analyses revealed that 2 h post-load plasma glucose values of ≥160 mg/dL was the only independent predictor of long-term MACE after AMI (p = 0.028, OR: 1.85, 95% CI: 1.07-3.21). The 2-year cardiac event rate of patients with a 2 h post-load hyperglycemia of ≥160 mg/dL was significantly higher than that of patients with 2 h post-load glucose of <160 mg/dL (32.2% vs. 19.8%, p < 0.05) and was similar to that of PDM group (37.4%, p = 0.513). CONCLUSIONS: NDM increases the risk of MACE after AMI as does PDM. Particularly, post-AMI patients with a 2 h post-load hyperglycemia ≥160 mg/dL may need adjunctive therapy after AMI.

Coronary vasospasm secondary to allergic reaction following food ingestion: a case of type I variant Kounis syndrome.

Coronary vasospasm can be induced by allergic reactions with some chemical mediators, and the angina and myocardial infarction secondary to allergy-induced coronary vasospasm are referred to as "Kounis syndrome." Only two cases of Kounis syndrome following food ingestion have been reported. However, they had pre-existing atheromatous coronary artery disease, and no provocation test to induce coronary vasospasm was done. We describe here another probable case of allergic vasospasm after food intake. To the best of our knowledge, this is the first documented report of a patient with food-induced allergic vasospasm subsequent to the provocation test with ergometrine maleate.

Sirolimus-eluting stent versus balloon angioplasty for sirolimus-eluting stent restenosis: Insights from the j-Cypher Registry.

BACKGROUND: Optimal treatment strategies for restenosis of sirolimus-eluting stents (SES) have not been adequately addressed yet. METHODS AND RESULTS: During the 3-year follow-up of 12 824 patients enrolled in the j-Cypher registry, 1456 lesions in 1298 patients underwent target-lesion revascularization (TLR). Excluding 362 lesions undergoing TLR for stent thrombosis or TLR using treatment modalities other than SES or balloon angioplasty (BA), 1094 lesions with SES-associated restenosis in 990 patients treated with either SES (537 lesions) or BA (557 lesions) constituted the study population for the analysis of recurrent TLR and stent thrombosis after the first TLR. Excluding 24 patients with both SES- and BA-treated lesions, 966 patients constituted the analysis set for the mortality outcome. Cumulative incidence of recurrent TLR in the SES-treated restenosis lesions was significantly lower than that in the BA-treated restenosis lesions (23.8% versus 37.7% at 2 years after the first TLR; P<0.0001). Among 33 baseline variables evaluated, only hemodialysis was identified to be the independent risk factor for recurrent TLR by a multivariable logistic regression analysis. After adjusting for confounders, repeated SES implantation was associated with a strong treatment effect in preventing recurrent TLR over BA (odds ratio, 0.44; 95% confidence interval, 0.32 to 0.61; P<0.0001). The 2-year mortality and stent thrombosis rates between the SES- and the BA-treated groups were 10.4% versus 10.8% (P=0.4) and 0.6% versus 0.6%, respectively. CONCLUSIONS: Repeated implantation of SES for SES-associated restenosis is more effective in preventing recurrent TLR than treatment with BA, without evidence of safety concerns.

A 3-year clinical outcome after percutaneous coronary intervention using sirolimus-eluting stent and off-pump coronary artery bypass grafting for the treatment of diabetic patients with multivessel disease.

BACKGROUND: There are few data to compare the long-term efficacy of sirolimus-eluting stent (SES) and off-pump coronary artery bypass grafting (OPCAB) for diabetic patients with multivessel disease (MVD). METHODS AND RESULTS: In a single-center non-randomized registry, 208 diabetic patients with MVD were examined (SES group: n=92, OPCAB group: n=116). The occurrence of major adverse cardiac and cerebrovascular events (MACCE, defined as all-cause death, non-fatal myocardial infarction, cerebrovascular event, and repeat revascularization) was compared between the 2 groups. Fasting blood glucose level, type of diabetic treatment and the prevalence of diabetic major vascular complications were similar between groups. The SES group had a significantly higher prevalence of 2-vessel disease and a significantly lower prevalence of 3-vessel disease compared with the OPCAB group. During the follow-up period (mean: 42+/-8 months), the rate of revascularization was significantly higher in the SES group than the OPCAB group (21% vs 6.9%, P=0.003). On the other hand, there was a significant higher occurrence of cerebrovascular events in the OPCAB group. Finally, the cumulative MACCE was similar between the 2 groups (27% vs 23%, P=0.492). CONCLUSIONS: At the 3-year clinical follow-up, the prevalence of MACCE in diabetic patients with MVD was comparable between the SES and the OPCAB groups.

Significant association between neutrophil aggregation in aspirated thrombus and myocardial damage in patients with ST-segment elevation acute myocardial infarction.

BACKGROUND: This study was designed to clarify the relationship between myocardial damage and platelet-neutrophil aggregation in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: The study group comprised 107 patients with ST-segment elevation AMI, in whom aspiration catheter was used during emergency percutaneous coronary intervention. Patients were divided into 2 groups according to the cellular density of neutrophils in the aspirated sample: group L (n=53), 100 neutrophils/0.025 mm(2) thrombus. Myocardial blush grade (MBG)

Inverted Takotsubo cardiomyopathy masking acute myocardial infarction.

We report a case of inverted Takotsubo cardiomyopathy masking acute myocardial infarction. In this case, echocardiography on admission showed left ventricular mid and basal akinesis and apical hyperkinesis compatible with an inverted Takotsubo contractile pattern. In the subacute phase, however, he was suspected of having acute myocardial infarction by serial changes of cardiac enzymes. After 8 days of admission, echocardiography showed normalization of the left ventricular contraction, except the inferior wall which was compatible with inferior myocardial infarction. Subsequent myocardial scintigraphy confirmed the diagnosis. It is important to recognize that inverted Takotsubo cardiomyopathy may mask acute myocardial infarction when they occur simultaneously.

Use of SafeCut Balloon for treatment of in-stent restenosis of a previously underexpanded sirolimus-eluting stent with a heavily calcified plaque.

Calcified lesions are a cause of stent underexpansion which significantly increases the subsequent risks of in-stent restenosis and thrombosis, even when drug-eluting stents are used. In this report, we describe a novel balloon catheter (SafeCut) that enabled adequate dilatation of in-stent restenosis in a previously underexpanded sirolimus-eluting stent that was unresponsive to high-pressure inflation using a conventional balloon after aggressive rotational atherectomy to treat a heavily calcified plaque.