Mechanisms, management, and outcome of failure of delivery of coronary stents.

In a single-center experience, initial failure of attempted stent delivery was relatively infrequent (2.7%) but was associated with increased need for urgent coronary bypass surgery. Delivery failure was more likely with coiled stents and dislodgment from the delivery balloon was more likely with hand-mounted or radiolucent stents.

Comparison of mortality rates and progression of left ventricular dysfunction in patients with idiopathic dilated cardiomyopathy and dilated versus nondilated right ventricular cavities.

This study assesses the influence of right ventricular (RV) dilation on the progression of left ventricular (LV) dysfunction and survival in patients with idiopathic dilated cardiomyopathy (IDC). Using transthoracic echocardiography, we studied 100 patients with IDC aged 20 to 80 years (mean 55 +/- 14); 67% were men. In the apical 4-chamber view, diastolic LV and RV chamber area measurements classified patients into 2 groups: group RV enlargement+ (RV area/LV area > 0.5) included 54 patients; group RV enlargement- (no RV enlargement) had RV area/LV area < or = 0.5. Echocardiographic studies were repeated in all patients after a mean of 33 +/- 16 months. At the time of the initial study, the 2 groups did not differ in age, gender, incidence of atrial fibrillation and diabetes, left ventricular mass, and LV ejection fraction, but the RV enlargement+ group had more severe tricuspid regurgitation and less LV enlargement. After 47 +/- 22 months (range 12 to 96), patients in group RV enlargement+ had lower LV ejection fraction (29% vs 34%, p = 0.006) than patients with initial RV enlargement-. At clinical follow-up, mortality was higher (43%) in patients with initial RV enlargement+ than the RV enlargement- patients (15%), p = 0.002. For survivors, the mitral deceleration time averaged 157 +/- 36 ms; for nonsurvivors or patients who required transplant, the mitral deceleration time averaged 97 +/- 12 ms (p < 0.0001). With use of a multivariate Cox model adjusting for LV ejection fraction, LV size, and age, the relative risk ratio of mortality from initial RV enlargement+ was 4.4 (95% confidence limits 1.7 to 11.1) (p = 0.002). Thus, patients with significant RV dilation had nearly triple the mortality over 4 years and more rapidly deteriorating LV function than patients with less initial RV dilation. In IDC, RV enlargement is a strong marker for adverse prognosis that may represent a different morphologic subset.

Correlation of remote ST segment depression and coronary anatomy during acute coronary occlusion.

BACKGROUND: The appearance of remote ST segment depression (RSTD) on an electrocardiogram (ECG) is associated with more extensive infarction and a worse clinical outcome than when RSTD is absent. OBJECTIVE: To determine whether RSTD predicts coronary anatomy during acute coronary occlusion. It was hypothesized that RSTD is associated with the occlusion of a proximal lesion, an extensive artery and an artery without distal collateralization. PATIENTS AND METHODS: In 113 consecutive patients with single vessel disease undergoing percutaneous transluminal coronary angioplasty (PTCA), 12-lead ECGs (recorded at baseline and during balloon inflation) and angiographical data were analyzed independently. Patients with ST segment elevation in the primary territory and RSTD (greater than 1 mm ST depression at 80 ms after the J point) (group A) were compared with patients without RSTD (group B). Proximal lesions were defined as lesions located in the segments proximal to the acute marginal branch, first diagonal artery or first obtuse marginal branch. An extensive right coronary artery (RCA) was one that supplied the posterolateral wall; an extensive left anterior descending (LAD) artery was one that supplied the inferoapical wall; and an extensive circumflex artery was one that supplied the posterior descending artery. RESULTS: Fifty-four patients (48%) had PTCA of the proximal vessels, 43 patients (38%) had extensive target vessels and 11 patients (9.7%) had collaterals. Target vessels included 33% in RCA, 44% in LAD artery and 23% in circumflex artery. Forty-five patients (40%) developed RSTD during balloon inflation (group A). Patients in group A were more likely to have extensive vessels on the angiogram than those in group B (group A 49%, group B 31%; P=0.05). None of the patients in group A had collaterals to the culprit artery, while 16% of patients in group B did (P=0.003). The two groups were not significantly different with respect to the number of proximal lesions (group A 58%, group B 42%; P=0.08). Analysis performed according to the target artery revealed that RSTD was associated with occlusion of an extensive RCA during RCA occlusion (extensive RCA in group A 100%, group B 57%; P=0.006). For the LAD artery, RSTD was associated with proximal lesions (group A 74%, group B 41%; P=0.02) and absence of collaterals (group A 100%, group B 74%; P=0.01). CONCLUSIONS: During acute coronary occlusion, the presence of RSTD on 12-lead ECG was specific for the absence of collaterals. The presence of RSTD during RCA occlusion was strongly associated with an extensive RCA, suggestive of posterolateral wall ischemia. During LAD artery occlusion, the presence of RSTD was associated with proximal occlusion, which resulted in ischemia of the LAD artery and the major diagonal artery territories.

Coronary stenting without predilatation in a broad spectrum of clinical and angiographic situations.

BACKGROUND: Direct coronary stenting without balloon predilatation has the potential benefits of a reduced risk of extended dissections, reduced fluoroscopy exposure, reduced procedural time, and potential cost savings. With the availability of superior stents and delivery systems, we review our experience with direct stent deployments in a large selected patient cohort. METHODS: We prospectively studied 158 consecutive cases of attempted coronary stenting without balloon predilatation over a 1-year period. RESULTS: Indications for the procedure included unstable angina (71%), stable angina (24%) and acute myocardial infarction (5%). Target vessels were the anterior descending artery (56%), right coronary artery (30%), circumflex artery (8%), and vein grafts (6%). Pre-procedural TIMI flows were grade 3 (91.7%), grade 2 (5.8%), grade 1 (1.3%) and 0 (1.3%). Lesion types were graded A (27%), B (61%), and C (12%). Stent types included NIR Primo (80.4%), ACS Multi-Link RX Duet (10.1%), NIR (5.1%), and others (4.4%). Stents ranged from 3.0Eth 4.0 mm in diameter (median = 3 mm) and 8Eth 32 mm in length (median = 16 mm). Stents were successfully deployed in 155 cases (98.1%); 2 (1.3%) required predilatation and 1 (0.6%) deployed stent could not be expanded and was opened by rotablation. All except the rotablator case achieved final TIMI grade 3 flow, and 66% did not require further balloon dilatation. There were no deaths or cases of urgent bypass surgery. Case duration and radiation exposure in direct stenting (32.8 +/- 18.9 minutes and 6.7 +/- 6.2 minutes, respectively) compared favorably to those in a matched group of patients in conventional stenting (47 +/- 18 minutes and 11 +/- 7 minutes) and coronary angioplasty (40 +/- 12 minutes and 10 +/- 6 minutes) for single-lesion cases (p < 0.005). Creatine kinase elevation related to the procedure was observed in 5 patients. Subacute stent thrombosis occurred in 2 (1.3%) cases. CONCLUSION: Direct coronary stenting was successfully and safely accomplished in a variety of clinical situations in selected patients.

Facilitation of stent retention and retrieval with an emboli containment device.

A potential consequence of unsuccessful stent delivery is dislodgment of the stent from the delivery catheter resulting in embolization. Recently, an angioplasty guidewire incorporating a distal occlusion balloon (GuardWire) has become available. We describe how, when used for the prevention of distal embolization of atheromatous or thrombotic particles, this device may facilitate retention and retrieval of undeployed stents.