Long-term clinical outcomes of drug-eluting stents vs bare-metal stents in Chinese patients.

BACKGROUND: There is limited data on the magnitude of the problem of drug-eluting stent (DES) thrombosis in the Asian population. HYPOTHESIS: We evaluated the long-term clinical outcomes of DES vs bare metal stents (BMS) in Chinese patients. METHODS: From January 2002 to October 2005, 1236 consecutive patients underwent percutaneous coronary intervention with DES or BMS coronary stent implantation at our institution. We analyzed major clinical end points like all-cause mortality, cardiovascular death, myocardial infarction, target lesion revascularization (TLR), and stent thrombosis. RESULTS: The 3-year cumulative rates of all-cause mortality, cardiovascular death, and myocardial infarction were significantly lower in the DES group (3.4%, 0.9%, 3.6%) when compared with the BMS group (7.5%, 4.4%, 6.2%; P < .05). No significant differences were found in the 3-year cumulative rates for TLR or stent thrombosis when comparing the DES group (8.3%, 1.63%) vs the BMS group (9.6%, 1.6%; P > .05). However, after 1 year, there were 8 episodes of stent thrombosis in the DES group vs 1 episode of stent thrombosis in the BMS group (P = .04). CONCLUSION: Drug-eluting stents are associated with a significant reduction in the 3-year cumulative rates of all-cause mortality, cardiovascular death, and myocardial infarction when compared to BMS. However, there were no significant differences in the cumulative rates of TLR or stent thrombosis at 3 years. Stent thrombosis after 1 year was more common in the DES group, but this did not translate to increased mortality. The suggestion that DES might confer a mortality benefit should be interpreted with caution as there could be several confounding factors that were not identified in our study.

Clinical implications of precordial ST-segment elevation in acute inferoposterior myocardial infarction caused by proximal right coronary artery occlusion.

BACKGROUND: The clinical significance of inferior wall acute myocardial infarction (MI) with combined ST-segment elevation in both anterior and inferior leads, compared with inferior leads alone, is unknown. HYPOTHESIS: Despite having more leads with precordial ST-segment elevation, these patients may have a better outcome due to less posterior involvement, which tends to drag down the precordial ST-segment. METHODS: A total of 158 postinferior MI patients with documented proximal right coronary artery occlusion were retrospectively studied. They were divided into three subgroups according to the magnitude of concurrent ST-segment deviation in lead V2: Group A (n = 19) had ST-segment elevation >/= 2.0 mm; Group B (n = 74) had ST-segment lay between + 2.0 mm and - 2.0 mm; and Group C (n = 65) had ST-segment depression >/= 2.0 mm. The clinical and electrocardiographic characteristics were then compared among these threes subgroups. RESULTS: The baseline demography, prevalence of risk factors, and treatment received were of no difference among the subgroups. However, Group A patients had significantly lower peak creatinine phosphokinase level and more preserved left ventricular function than Group B and C. Moreover, they had lower total sum of inferior ST-segment magnitude, less ST-segment depression in V4-6, and more ST-segment elevation in V(4R) than Group C. Group C patients had highest in-hospital and one-year mortality although it did not reach statistical significance. CONCLUSIONS: Precordial ST-segment elevation in inferior wall acute MI was associated with smaller infarct size and better left ventricular function, probably secondary to occlusion of a less dominant RCA, which did not result in a significant posterior infarction.

Transient atrial fibrillation complicating acute inferior myocardial infarction: implications for future risk of ischemic stroke.

BACKGROUND: Atrial fibrillation (AF) that occurs as a frequent complication of myocardial infarction (MI) is associated with a poor clinical outcome. It nonetheless remains uncertain whether AF that occurs transiently during MI is associated with a subsequent increased risk of the development of AF and ischemic stroke. METHODS: We retrospectively studied the impact of transient AF on the long-term risk of the occurrence of AF, ischemic stroke, and mortality in 431 consecutive patients (mean [+/- SEM] age, 64 +/- 1 years; 75% men). All patients had experienced an acute inferior ST-segment-elevation MI and had preserved left ventricular ejection fraction (LVEF) [> 45%]. RESULTS: All patients were in sinus rhythm on hospital admission, and transient AF was observed in 59 patients (13.7%) during their hospitalization for MI. On hospital discharge, all patients were in sinus rhythm and had been prescribed antiplatelet agents alone as antithrombotic therapy. Patients in whom transient AF developed during MI were older (mean age, 70 +/- 1.4 vs 64 +/- 0.7 years, respectively; p < 0.01) and more likely to be women (37% vs 23%, respectively; p < 0.02) compared with those without AF. At 1-year follow-up, the incidence of AF (22.0% vs 1.3%, respectively; p < 0.01) and ischemic stroke (10.2% vs 1.8%, respectively; p < 0.01) was higher in patients with transient AF than in those without transient AF. The total mortality rate was nonetheless similar (5.6% vs 6.8%, respectively; p = 0.73); Cox regression analysis demonstrated that age > 65 years and transient AF during MI were independent predictors of the subsequent occurrence of AF and the development of ischemic stroke. CONCLUSION: Transient AF complicating acute inferior MI is associated with an increased future risk of AF occurrence and ischemic stroke in patients with preserved LVEF, despite the use of antiplatelet therapy.

Value of ST-segment depression in lead V4R in predicting proximal against distal left circumflex artery occlusion in acute inferoposterior myocardial infarction.

BACKGROUND: Lead V(4R) faces the right ventricular free wall; it also reflects ischemia in the posterolateral wall lying opposite and manifests as ST-segment depression. HYPOTHESIS: The aim of this study was to evaluate the usefulness of V(4R) ST-segment depression in distinguishing proximal from distal left circumflex artery occlusion in acute inferoposterior wall myocardial infarction. METHODS: We retrospectively analyzed 239 patients who had first acute inferoposterior myocardial infarction, were admitted within 6 h from onset of symptom, and had coronary angiography performed within 4 weeks. Patients who had bundle-branch block or concomitant significant stenoses in the proximal and distal segments of the same vessel or of both vessels were excluded. The electrocardiographic and angiographic findings were reviewed by two independent groups of investigators. RESULTS: V(4R) ST-segment depression > or =1.0 mm was found in 8 of 46 patients (17.4%) with left circumflex artery occlusion but none (0%) with right coronary artery occlusion. Among the group with left circumflex artery occlusion, the mean magnitude of V(4R) ST-segment depression was greater in proximal than distal occlusion (0.82 +/- 0.65 vs. 0.03 +/- 0.12 mm, p < 0.0001). V(4R)ST-segment depression > or =1.0 mm was found in 8 of 14 patients (57.1%) with proximal occlusion but none (0%) in 32 patients with distal occlusion. The sensitivity and specificity to predict proximal occlusion were 57.1 and 100%, respectively. CONCLUSIONS: V(4R) ST-segment depression > or =1.0 mm was not useful for differentiating left circumflex and right coronary artery occlusion because of its low sensitivity. It is a fairly sensitive and very specific sign of proximal left circumflex artery occlusion.

Modified crush technique with double kissing balloon inflation (sleeve technique): a novel technique for coronary bifurcation lesions.

We report a modified crush technique with double kissing balloon inflation (the sleeve technique) in an attempt to increase the success rate of final kissing balloon inflation, which has been shown to improve the angiographic outcomes of side branch in bifurcation lesions. A stent was advanced across the side branch with protrusion of 3-5 mm of proximal stent segment into the main vessel. At the same time, a size-matched balloon with length long enough to cover the bifurcation as well as the protruding stent segment was placed in the main vessel. The side-branch stent is deployed first, the wire and stent balloon are removed. This is followed by balloon inflation in main vessel at high pressure to crush the protruding stent segment against vessel wall. The side branch is then rewired, two balloons are advanced to the main vessel and side branch, and the bifurcation is kissed with balloons the first time. The side branch is now like a new sleeve. The balloon and wire of the side branch are removed. Another stent was positioned and then deployed in the main vessel. The side branch is rewired the second time, two balloons are advanced to the main vessel and side branch again, followed by final (second) kissing balloon inflation of the bifurcation. The sleeve technique has been employed in six consecutive patients with 100% success rate of final kissing balloon inflation. There was no major adverse cardiac events or stent thrombosis encountered within 30 days of percutaneous coronary intervention.

Anomalous origin of right coronary artery from the left coronary sinus: incidence, characteristics, and a systematic approach for rapid diagnosis.

Twenty-three patients were found to have anomalous origin of right coronary artery from the left coronary sinus (LCS) from January 2000 to October 2003. The mean age was 58.6+/-14.3 years with male predominance (56.5%). Cardiovascular risk factors were found in 18 (78.3%) patients while coronary artery disease was seen in 13 (56.5%) patients. Among the coronary artery disease patients, the left anterior descending artery was the most commonly involved, followed by the right coronary artery and the left circumflex artery. Right coronary artery dominance was seen in 19 (82.6%) patients. The anomalous right coronary artery originates within the left coronary sinus in 17 (73.9%) patients while from the left aortic wall above the sinus in 6 (26.1%) patients only. Congenital heart disease and acquired valvular heart disease were the most common associated conditions. The author will share his experience and suggest a four-step approach of early recognition and selection of the anomalous right coronary artery ostium. Using the suggested strategy, most of the anomalous right coronary artery could be opacified with a left amplatz 1 catheter. Aortogram was needed only in 47.8% of cases.

Effect of a cardiac rehabilitation program on left ventricular diastolic function and its relationship to exercise capacity in patients with coronary heart disease: experience from a randomized, controlled study.

BACKGROUND: A cardiac rehabilitation and prevention program (CRPP) is a recognized nonpharmacological modality in the management of coronary heart disease (CHD). However, the effect of a CRPP on systolic function of the heart is controversial, and no data exists on diastolic function in CHD. A randomized, controlled study was conducted to address these issues. METHODS: Patients (n = 269) with recent acute myocardial infarction (n = 193) or after percutaneous coronary intervention (PCI) (n = 76) were randomized to either CRPP (2-hour twice-weekly exercise program for 8 weeks) or conventional therapy (control group). Serial treadmill exercise testing and at-rest echocardiography were performed during phases 1 (baseline), 2 (post-exercise training), and 3 (8-month follow up). RESULTS: The prevalence of left ventricular (LV) abnormal relaxation pattern (ARP) of diastolic dysfunction was increased in the control group only in phase 3 (65% vs 88%, chi2 = 7.6, P <.01). Significant improvement of individual LV diastolic parameters towards less severe delayed relaxation was also observed in the CRPP group, especially in those with recent acute myocardial infarction or ARP. The gain in exercise capacity was faster and more substantial in the CRPP than the control group (P <.001 for phase 2, P <.05 for phase 3), and was significantly correlated with LV diastolic indices in those with ARP. Exercise training had neutral effects on LV systolic function and rate-pressure product. CONCLUSIONS: In patients with CHD, CRPP prevented the progression of resting LV diastolic dysfunction, without affecting systolic function. In those with ARP, the improvement of diastolic function predicted the gain in exercise capacity.

A new technique for the transvenous implantation of the over-the-wire left ventricular pacing lead in a patient with heart failure.

Implantation of left ventricular leads (LV) for biventricular pacing remains a technological challenge and failure of the procedure is not uncommon. We described a 58 year-old patient with heart failure and intraventricular conduction delay where difficulty is encountered when cannulating the coronary sinus by the guiding catheter. By placing a guiding catheter in the inferior portion of the right atrium, a coronary guidewire, preloaded with an over-the-wire lead system, was used to reach the lateral cardiac vein. This may help to reduce the implant failure rate and avoid other more invasive means of LV lead implantation.