Primary stenting versus balloon angioplasty in occluded coronary arteries: the Total Occlusion Study of Canada (TOSCA).

BACKGROUND: Balloon angioplasty (PTCA) of occluded coronary arteries is limited by high rates of restenosis and reocclusion. Although stenting improves results in anatomically simple occlusions, its effect on patency and clinical outcome in a broadly selected population with occluded coronary arteries is unknown. METHODS AND RESULTS: Eighteen centers randomized 410 patients with nonacute native coronary occlusions to PTCA or primary stenting with the heparin-coated Palmaz-Schatz stent. The primary end point, failure of sustained patency, was determined at 6-month angiography. Repeat target-vessel revascularization, adverse cardiovascular events, and angiographic restenosis (>50% diameter stenosis) constituted secondary end points. Sixty percent of patients had occlusions of >6 weeks' duration, baseline flow was TIMI grade 0 in 64%, and median treated segment length was 30.5 mm. With 95.6% angiographic follow-up, primary stenting resulted in a 44% reduction in failed patency (10.9% versus 19.5%, P=0.024) and a 45% reduction in clinically driven target-vessel revascularization at 6 months (15.4% versus 8.4%, P=0.03). The incidence of adverse cardiovascular events was similar for both strategies (PTCA, 23.6%; stent, 23.3%; P=NS). Stenting resulted in a larger mean 6-month minimum lumen dimension (1.48 versus 1.23 mm, P<0.01) and a reduced binary restenosis rate (55% versus 70%, P<0.01). CONCLUSIONS: Primary stenting of broadly selected nonacute coronary occlusions is superior to PTCA alone, improving late patency and reducing restenosis and target-vessel revascularization.

Ventricular entrapment of a Swan-Ganz catheter: a technique for nonsurgical removal.

Entrapment of a balloon-tipped flow-directed catheter by atrial sutures during open heart surgery is a rare but serious complication. Several methods have been used to free such catheters with nonsurgical techniques. A case of entrapment in the right ventricle after repair of a ventricular septal defect is presented and a method for percutaneous removal described.

Isolated chronic mitral regurgitation with preserved systolic left ventricular function and severe pulmonary hypertension.

Pulmonary hypertension in chronic mitral valve disease has been related most commonly to left ventricular dysfunction or mitral stenosis; its association with chronic, isolated mitral regurgitation and preserved left ventricular systolic function is unclear. In 41 catheterized patients with chronic mitral regurgitation (known history of mitral regurgitation for greater than 18 months) and preserved left ventricular systolic function (ejection fraction greater than 0.55), historic, electrocardiographic, echocardiographic and hemodynamic variables were analyzed. Ten patients (Group I) had normal pulmonary artery systolic pressure (less than 30 mm Hg), whereas 31 patients had pulmonary hypertension. Pulmonary artery systolic pressure was mildly increased (30 to 49 mm Hg) in 13 patients (Group II) and was greater than or equal to 50 mm Hg in 18 patients (Group III). Univariate analysis showed the more frequent occurrence of male gender and ruptured chordae tendineae in the groups with pulmonary hypertension. Mean pulmonary capillary wedge pressure, size of the V wave in pulmonary capillary wedge pressure and pulmonary arteriole resistance were higher, whereas cardiac index was lower in the hypertension groups. Multivariate stepwise analysis revealed higher mean pulmonary capillary wedge pressure and pulmonary arteriole resistance as the only variables independently differing among groups. In conclusion, pulmonary hypertension occurs frequently (76% of cases) in patients with chronic, isolated mitral regurgitation with preserved left ventricular systolic function. In these patients, a severe increase in pulmonary capillary wedge pressure is associated with elevation in pulmonary artery resistance, a finding similar to that in mitral stenosis.

Percutaneous catheter closure of the persistently patent ductus arteriosus in the adult.

The USCI patent ductus occluder has been shown to be an effective nonsurgical technique for closure of the persistently patent ductus in a primarily pediatric population. Its clinical impact in the adult has been reported only within small subgroups of larger pediatric studies or for a small population. This study was conducted to determine the feasibility, success rate, and complications of device closure for the persistently patent ductus arteriosus (PDA) in the adult. The population consisted of 55 patients (4 men and 51 women; mean age 38.8 +/- 15.0 years) with follow-up of 2.2 +/- 2.1 years. All patients underwent echocardiography obtained as part of their follow-up assessment. The device was successfully placed in 54 patients, with 75% clinical and echocardiographic closure at the first follow-up assessment 2.4 +/- 2.6 months). One patient with initial clinical and echocardiographic evidence of closure was subsequently found to have an open ductus. Spontaneous closure (2 patients) or second implant (6 patients) resulted in 86% closure at the most recent assessment. Thus, the percutaneous PDA double-umbrella occluder device is a feasible and effective technique for closing persistent PDA in the adult and will result in occlusion of the shunt in most patients without the need for thoracotomy.

Angiosarcoma of the left atrium mimicking myxoma: case report.

The case of a 65-year-old female patient with a pedunculated left atrial angiosarcoma is presented. Histologically, the tumor was composed of vascular spaces lined by atypical cells with similar cells in the solid portion of the tumor. Immunohistochemical stain for factor VIII-related antigen was positive in the cells forming vascular spaces. Immunoperoxidase stain for Ulex Europaeus I lectin was positive in cells lining vascular lumina and in individual cells in the solid portion of the tumor. Cardiac angiosarcomas characteristically occur in men, arise in the right atrium, are large mural masses that infiltrate widely at the time of presentation, and are usually rapidly fatal. Review of the literature reveals that this case of cardiac angiosarcoma is unusual by virtue of its occurrence in a female, left atrial location as a polypoid lesion, and prolonged symptom-free survival after surgical resection alone. Cardiac angiosarcoma may clinically and radiologically simulate myxoma.

Predictors of survival of in-hospital cardiac arrest.

A prospective study was conducted of all cases of attempted resuscitation following cardiac arrest occurring over a period of one year in a tertiary care teaching hospital. Analysis was made of the effects on survival of preselected variables of patients and circumstances of arrest. In 125 cases for which resuscitation was attempted, 49 attempts (39%) were initially successful. Twenty-three patients were discharged from hospital (18% overall survival). The most potent predictors of successful resuscitation were early successful resuscitation (less than 20 mins), age less than 75 years, and cardiac arrest in proximity to an acute ischemic cardiac event (less than 48 h). Survival to discharge was extremely poor when the arrest was unwitnessed (zero of 20 cases) or when the arrest occurred on medical or surgical wards (two of 62 cases). Such low efficacy indicates that reassessment of policy regarding the administration of cardiac resuscitation to patients in hospital is warranted.

Coronary 'Y' stenting: a technique for angioplasty of bifurcation stenoses.

This report describes a case of successful percutaneous coronary transluminal angioplasty (PTCA) of a coronary artery bifurcating lesion using multiple intracoronary stents in an inverted 'Y' configuration. Balloon angioplasty of bifurcation coronary stenoses has a lower procedural success rate, higher restenosis rate and potential for side branch occlusion compared with nonbifurcation lesions. Numerous techniques, including two ('kissing') angioplasty balloons, have been used to overcome these problems. The authors believe that the technique described in this report, inserting stents into both branches simultaneously followed by a third proximal stent in a 'Y' configuration, allows successful dilatation of the bifurcation lesion while preserving flow into both branches and should be considered for similar complex anatomical subsets.

Comparing angiographic coronary revascularization strategies: a 'natural' experiment.

OBJECTIVE: To study the impact of intracoronary stents on clinical restenosis in the 'real world'. DESIGN: Retrospective comparison of the rates of clinical restenosis between two cohorts exposed to different strategies for percutaneous transcatheter intervention. The endpoint was the first of death, myocardial infarction, coronary artery bypass grafting, repeat percutaneous transluminal coronary angioplasty (PTCA) or repeat coronary angiography within nine months. SETTING: Tertiary care cardiac referral centre serving a large, metropolitan population. PATIENTS: Patients undergoing angiographic revascularization from January 1 to February 28, 1996 (the 'restricted' group [R], n=147) were compared with a before and after cohort (the 'usual' group [U], n=232, divided into those who underwent revascularization between November 1 and November 30, 1995, and those who underwent revascularization between April 1 and May 31, 1996). INTERVENTIONS: The R group was revascularized during a period of economic constraint, which imposed a shortage on stent availability. The U cohort underwent revascularization before and after the shortage (an 'unrestricted' environment for stent usage). MAIN RESULTS: There was no difference in clinical restenosis rates between the R (34.7%) and U (37.9%) groups (P=0.524, OR R/U=0.915, 95% CI 0.694 to 1.206). Also, the rate of clinical restenosis was the same among patients who underwent PTCA without stent insertion (34.8%) and those who received a stent (39.4%) (P=0.368, OR=1.13, 95% CI 0.87 to 1.44). CONCLUSIONS: At the authors' institution, a restricted stenting policy did not result in a higher clinical restenosis rate than that of usual practice.

Stenting for pulmonary artery stenosis following the Ross procedure.

A 34-year-old woman showed the development of significant main pulmonary artery obstruction along the supravalvar suture line 18 months following a Ross procedure. The patient underwent unsuccessful balloon angioplasty, followed by successful stent implantation. The angiographic narrowing disappeared postprocedure, and the excellent hemodynamic result maintained at 4 month follow-up.

Balloon valvuloplasty in adult aortic stenosis: determinants of clinical outcome.

STUDY OBJECTIVE: To determine the clinical variables affecting outcome after balloon aortic valvuloplasty. DESIGN: Longitudinal follow-up of consecutive case series. PATIENTS: Consecutive sample of 36 patients with severe calcific aortic stenosis, and without active infection or left ventricular mural thrombus. INTERVENTIONS: Percutaneous transluminal dilatation of the aortic valve until the peak gradient was reduced by 50% or a maximal balloon size was used. Hemodynamic measurements taken before and after dilatation. MEASUREMENTS AND MAIN RESULTS: Thirty-three patients had a successful dilatation. Eighty-nine percent (95% confidence interval [CI]. 74% to 97%) improved symptomatically at 2 weeks, but by 26 weeks only 56% (CI, 35% to 76%) remained improved (P = 0.0078). Mortality rates were high at 8 (9%) and 26 (28%) weeks. Predictors of adverse events included left ventricular ejection fraction (P = 0.04, r = 0.46), pulmonary artery systolic pressure (P = 0.048, r = 0.65), pulmonary vascular resistance (P = 0.008, r = 0.69), and right ventricular end-diastolic pressure (P = 0.009, r = 0.43) at 8 weeks and all these factors except left ventricular ejection fraction at 26 weeks. These clinical outcomes were unrelated to other cardiac or pulmonary diseases. CONCLUSIONS: Symptomatic improvement is only temporary in many patients undergoing balloon aortic valvuloplasty, and the mortality rate in the mid-term follow-up period is high. Valve surgery remains the treatment of choice for aortic stenosis in the adult.

Impaired vascular reactivity following angioplasty is mainly due to endothelial injury.

Vasoconstriction occurs frequently following coronary angioplasty and is implicated in the pathogenesis of abrupt closure and restenosis. Control of vasomotor tone is regulated in part directly by smooth muscle cells and indirectly through the endothelium. To study the mechanisms underlying vasoconstriction, the effect of angioplasty and endothelial denudation on endothelium-dependent and -independent relaxation was examined in 15 mongrel dogs. Percutaneous transluminal angioplasty and endothelial denudation of the right femoral artery were performed. Endothelial injury was assessed by adhesion of indium-111-labeled platelets. Endothelium-dependent and -independent relaxation were assessed using acetylcholine and nitroglycerin, respectively. Vessels precontracted with potassium chloride and exposed to acetylcholine showed impaired relaxation in both the angioplasty and denuded groups (angioplasty = 14 +/- 5%, denuded = 0 +/- 0%, normal = 73 +/- 12%; P less than 0.05 for both angioplasty and denuded compared to normal). Precontraction with phenylephrine yielded similar results (angioplasty = 16 +/- 8%, denuded = 4 +/- 2%, normal = 39 +/- 10%; P less than 0.05 only for denuded segment compared to normal). Segments precontracted with phenylephrine and exposed to nitroglycerin did not demonstrate impaired relaxation (angioplasty = 73 +/- 9%, denuded = 68 +/- 9%, normal = 71 +/- 7%, P = ns). Mean indium-111 counts were similar in both the angioplasty and denuded segments (2820 +/- 1481 and 2963 +/- 1228 counts/min/g, respectively) compared to a lower count in the normal segment (1514 +/- 956 counts/min/g). Thus, angioplasty produces significant vascular injury and impairment of vasodilator function, comparable to that caused by endothelial denudation alone. This implies that vasoconstriction seen following coronary angioplasty may be due to endothelial injury and the resultant loss of control of vasomotor tone.

Endovascular stents in the management of coarctation of the aorta in the adolescent and adult: one year follow up.

OBJECTIVES: To test the hypothesis that endovascular stents used with dilation of coarctation of the aorta (CoA) improve late outcomes. Balloon dilation for CoA has been limited by concerns over the risk for acute dissection, late restenosis, or aneurysm formation. DESIGN: All patients seen with CoA between November 1994 and September 1997 underwent attempted stent implantation. Follow up was obtained for all patients and a subgroup (n = 18) had repeat catheterisation at a mean (SD) of 1.3 (0.5) years to assess residual gradient and stent-CoA morphology. RESULTS: Stents were placed in 27 patients (15 male and 12 female patients, mean age 30.1 (13.1) years), of whom seven had prior surgical coarctectomy and one had a prior balloon dilation. Hypertension was present in 26 patients (mean pressure 164 (26)/86 (13) mm Hg), of whom 16 were on antihypertension drugs. CoA gradients were 46 (20) mm Hg (range 18-106 mm Hg) at baseline and 3 (5) mm Hg after the procedure. One patient had a stroke following the procedure; another patient had incomplete dilation and underwent a second procedure. At 1.8 (1) years after the procedure the mean pressure was 130 (14)/74 (11) mm Hg with seven patients on antihypertension treatment. The clinical gradient was 4 (8) mm Hg (range 0-32 mm Hg). At follow up angiography, the mean gradient was 4(6) mm Hg, and two patients had a gradient over 10 mm Hg. Aneurysms formed in three patients at the dilation site; one patient was referred for surgery. CONCLUSION: In this age group stent management for CoA appears to be an effective technique and results in sustained reduction in CoA gradients at early term follow up, but aortic aneurysm was detected in 17% of patients who had repeat angiography.

Stenting of coronary artery stenosis in Kawasaki disease.

Coronary artery lesions can develop in Kawaski disease as a major complication, and result in aneurysm formation and stenosis. Reported is the evolution of important coronary artery stenosis in a pediatric patient managed with an endovascular stent.

Bleeding risks with abciximab after full-dose thrombolysis in rescue or urgent angioplasty for acute myocardial infarction.

BACKGROUND: The bleeding risk associated with platelet glycoprotein IIb/IIIa inhibition in patients undergoing percutaneous transluminal coronary angioplasty (PTCA) after full-dose thrombolysis for acute myocardial infarction (AMI) is unclear. We examined the risk and predictors of bleeding complications in patients with AMI who received abciximab during rescue or urgent PTCA after full-dose thrombolytic therapy. METHODS: A multicenter retrospective cohort of 147 consecutive patients who underwent PTCA within 48 hours after full-dose thrombolysis for AMI was studied. Bleeding events (major, minor, nuisance) from the onset of AMI to discharge were compared between those who received abciximab (n = 57) and those who did not (n = 90). RESULTS: Baseline clinical characteristics were similar between the two groups. Despite lower doses of procedural heparin, the incidence of non-coronary artery bypass graft-related major and minor bleeding was higher in the abciximab group than in controls (63% vs 39%, P =.004). Although the risk of major bleeding was 4-fold with abciximab (12% vs 3%, P =.04), only one intracranial and one fatal bleeding event occurred. Multivariable regression identified abciximab therapy as the most powerful independent predictor of combined major and minor bleeding, with a hazard risk ratio of 1.9 (P =.04). CONCLUSIONS: In the setting of rescue or urgent PTCA within 48 hours after full-dose thrombolytic therapy after AMI, major and particularly minor bleeding were frequently encountered. The adjunctive use of abciximab increased these bleeding risks by approximately 2-fold.

Failed coronary stent deployment.

BACKGROUND: Coronary stent deployment failure may be more common in clinical practice than generally appreciated. The incidence of failed deployment in routine clinical practice and the clinical sequelae have not been described. This study sought to determine the incidence and consequences of failed coronary stent deployment and to identify clinical and angiographic characteristics associated with deployment failure. METHODS AND RESULTS: A series of 1303 consecutive procedures involving attempted coronary stenting were reviewed retrospectively. Failed stent deployment was defined as failure of the stent to be either delivered to or adequately deployed at the target lesion site. Clinical records and angiograms were reviewed and qualitative coronary angiography was performed for all cases of failed deployment. Deployment was unsuccessful in 108 (8.3%) cases involving 134 stents. Stenting was attempted as a primary procedure in 40%, as bailout in 18%, and for suboptimal angioplasty in 43% of cases. In 87% of cases, attempts were made to withdraw the stent from the coronary artery. Stent retrieval was successful in 45%, peripheral embolization occurred in 38% of patients, and in 4% the stent dislodged in the left main artery. In 35% of cases, additional stent(s) were successfully deployed. Deployment failure was associated with an overall in-hospital adverse outcome in 19% of patients, including 16% urgent coronary artery bypass grafting, 5% nonfatal myocardial infarction, and 3 in-hospital deaths. At 6-month follow-up, 39% of patients had had at least 1 adverse clinical outcome of death, myocardial infarction, or repeat target lesion revascularization. CONCLUSIONS: Failure to deploy stents is a serious and relatively common problem that is associated with significant morbidity and mortality rates. Improved deployment strategies, including new stent designs, are required to improve procedural outcomes.

Predictors of improvement in left ventricular function after percutaneous revascularization of occluded coronary arteries: a report from the Total Occlusion Study of Canada (TOSCA).

BACKGROUND: The Total Occlusion Study of Canada (TOSCA) is a multicenter, randomized trial evaluating the effect of stenting with > =1 heparin-coated stent on long-term patency after percutaneous coronary intervention by balloon angioplasty of occluded coronary arteries. The purpose of the current study was to compare the effect of stenting and balloon angioplasty on global left ventricular ejection fraction (LVEF) and regional wall motion and to examine what clinical and angiographic factors may have an effect on left ventricular function in this setting. METHODS AND RESULTS: Analysis at the core angiographic laboratory of paired baseline and follow-up left ventricular angiograms, as well as target vessel patency, was possible in 244 of 410 cases. An improvement in LVEF was observed in the entire group (59.4% +/- 11% to 61.0% +/- 11%, P =.003). The LVEF change was +1.84 +/- 7.54 in the stent group (P =.009) and 1.28 +/- 8.16 in the percutaneous transluminal coronary angioplasty group (P =.085). There was no significant intergroup difference. Patients with duration of occlusion < or =6 weeks had an improvement in LVEF (+2.98 +/- 8.68, P =.0006), whereas those with an occlusion duration of > 6 weeks had no improvement (+0.48 +/- 7.01, P not significant). Multivariate analysis revealed baseline LVEF <60%, duration of occlusion < or =6 weeks, and Canadian Cardiology Society angina class I or II to be independent predictors of improvement in LVEF. CONCLUSIONS: The restoration of coronary patency of nonacute occluded coronary arteries is associated with a small but significant improvement in regional and global left ventricular function, especially in patients with recent occlusions and depressed left ventricular function. In spite of significant effect on long-term patency, stenting of nonacute coronary occlusions does not result in significantly better left ventricular function compared with balloon angioplasty in this setting.