Percutaneous patent foramen ovale closure: outcomes with the Premere and Amplatzer devices.

BACKGROUND: Transcatheter closure of patent foramen ovale (PFO) has rapidly evolved as the preferred management strategy for the prevention of recurrent cerebrovascular events in patients with cryptogenic stroke and presumed paradoxical embolus. There is limited outcome data in patients treated with this therapy particularly for the newer devices. METHODS: Data from medical records, catheter, and echocardiography databases on 70 PFO procedures performed was collected prospectively. RESULTS: The cohort consisted of 70 patients (mean age 43.6 years, range 19 to 77 years), of whom 51% were male. The indications for closure were cryptogenic cerebrovascular accident (CVA) or transient ischemic attack (TIA) in 64 (91%) and peripheral emboli in two (2.8%) patients and cryptogenic ST-elevation myocardial infarction in one (1.4%), refractory migraine in one (1.4%), decompression sickness in one (1.4%), and orthodeoxia in one (1.4%) patient, respectively. All patients had demonstrated right-to-left shunting on bubble study. The procedures were guided by intracardiac echocardiography in 53%, transesophageal echocardiography in 39%, and the remainder by transthoracic echo alone. Devices used were the Amplatzer PFO Occluder (AGA Medical) (sizes 18-35 mm) in 49 (70%) and the Premere device (St. Jude Medical) in 21 (30%). In-hospital complications consisted of one significant groin hematoma with skin infection. Echocardiographic follow-up at 6 months revealed that most patients had no or trivial residual shunt (98.6%), while one patient (1.4%) had a mild residual shunt. At a median of 11 months' follow-up (range 1 month to 4.3 years), no patients (0%) experienced further CVA/TIAs or paradoxical embolic events during follow-up. CONCLUSION: PFO causing presumed paradoxical embolism can be closed percutaneously with a low rate of significant residual shunting and very few complications. Recurrent index events are uncommon at medium-term (up to 4 years) follow-up.

The relative atrial index (RAI)--a novel, simple, reliable, and robust transthoracic echocardiographic indicator of atrial defects.

BACKGROUND: The detection of atrial septal defects (ASDs) and other shunts is sometimes difficult on transthoracic echocardiography. In addition, the quantitative assessment of right-heart volume loading as an indicator of significant shunting can be difficult, with subjective estimation commonly used. Thus, the initial aim of this study was to test the accuracy of a simple, noninvasive index using atrial area dimensions to detect the presence of an ASD. Subsequently, the index was used to assess the degree of normalization and remodeling of atrial size following percutaneous ASD device closure. METHODS: The relative atrial index (RAI) was derived from standard apical 4-chamber views as right atrial area divided by left atrial area. RAI was calculated in patients with previously diagnosed secundum atrial defects (n=219) with no concomitant lesions and then compared with those calculated in age-matched controls (n=219). 101 of the 219 patients with secundum atrial defects underwent percutaneous device closure. Measurements were obtained before and 1 day after percutaneous closure as well as in the early (mean, 124 days) and late (mean, 390 days) stages of follow-up. RESULTS: The mean RAI in patients with ASDs (1.23+/-0.23) was significantly higher than that in the age-matched normal control group (0.78+/-0.1) (P<.0001). The mean RAI in patients with ASD was also significantly higher than that in the general population (0.81+/-0.15) (P<.0001). Receiver operating characteristic curve analysis suggested that a nominal RAI cutoff value of >0.92 predicted patients with ASDs versus matched controls with 99.1% sensitivity and 90.5% specificity. After percutaneous closure, significant atrial remodeling occurred immediately, with a reduction in the mean RAI at day 1 to 0.93+/-0.16 (P<.0001) and complete normalization at early follow-up to 0.81+/-0.12. CONCLUSION: The RAI, a novel and simple transthoracic parameter, reliably identifies patients with possible atrial shunting. The resolution of right atrial enlargement occurs remarkably early after percutaneous ASD closure, as demonstrated by this novel parameter.

Ventricular septal rupture following nonsurgical septal reduction for hypertrophic cardiomyopathy: treatment with percutaneous closure.

An 82-year-old woman with severe symptomatic hypertrophic obstructive cardiomyopathy undergoes nonsurgical septal reduction, leading to immediate hemodynamic and functional improvement. Five weeks later, she presents with severe biventricular failure due to a large septal rupture with marked left-to-right shunting. The rupture is closed with an Amplatzer post-MI ventricular septal defect occluding device. Residual shunting through the device and a small residual shunt at its superior rim lead to severe hemolysis, which resolves spontaneously after 10 days of supportive therapy. A further self-limiting episode of hemolysis recurred 3 months later following a period of excessive anticoagulation.

Transthoracic left ventricular puncture for the assessment of patients with aortic and mitral valve prostheses: the Massachusetts General Hospital experience, 1989-2000.

Accurate assessment of suspected prosthetic valve dysfunction is critically important as reoperation carries high risk. Noninvasive methods of hemodynamic assessment of patients with both aortic and mitral mechanical valves continue to be frustrated by the interference created by prosthetic material and direct left ventricular puncture may be required for definitive hemodynamic assessment. We report the hemodynamic and angiographic results and outcomes of 38 consecutive patients with double valve replacement who underwent left ventricular puncture as part of evaluation of possible prosthetic dysfunction. These results were compared with those obtained by noninvasive testing. We found noninvasive assessment alone to be unsatisfactory as measurements of regurgitation and stenosis correlated poorly with those obtained by direct left ventricular puncture. Important information that altered patient management was obtained from invasive assessment in 68% of cases with an acceptable rate of complications. Therefore, hemodynamic and angiographic assessment using transthoracic left ventricular puncture should be entertained in patients with mitral and aortic valve replacement presenting with congestive heart failure and suspected prosthesis dysfunction.

Heparin-induced thrombocytopenia: a common complication in cardiac transplant recipients.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is an idiosyncratic complication of heparin therapy triggered by the development of immunoglobulin G (IgG) antibodies to platelet factor 4 heparin. It typically results in a 50% decrease in platelet count. Paradoxically, although bleeding is rare, there is a high risk of venous or arterial thrombotic events. Given that many patients awaiting transplantation are exposed to heparin for prolonged periods, we sought to determine the frequency of HIT and its consequences among patients before and after cardiac transplantation. METHODS: We reviewed retrospectively the clinical, pathologic, and laboratory databases for all patients who underwent heart transplantation at our institution between January 1, 1998, and December 31, 2000. An enzyme-linked immunoabsorption assay (ELISA) that detected IgG, IgA, and IgM antibodies directed against platelet factor 4 heparin complex confirmed the diagnosis of HIT. We analyzed bleeding and thrombotic complications and determined the influence of HIT on post-transplant outcomes. RESULTS: An assay for HIT antibody was performed before or after transplantation in 26 of 46 patients (46% of the entire cohort). In all cases, the clinical indication for testing was thrombocytopenia. Among patients screened, HIT antibody was detected in 11 patients (39%); HIT developed in 10 of 11 patients before transplantation. The mean platelet count at diagnosis was 88,000 +/- 22,000/mm(3). Heparin-induced thrombocytopenia with thrombosis syndrome developed in 5 of 11 patients (45%). Manifestations included splenic and renal infarctions, renal artery occlusion, coronary artery embolism with myocardial infarction, pulmonary embolism, and femoral and jugular venous occlusions. Alternative pre-operative anti-coagulation included lepirudin (n = 7), argatroban (n = 1), dalteparin (n = 1), and abciximab (n = 1). Two deaths occurred in the HIT-positive group; neither bleeding nor thrombosis caused either death. Actuarial 36-month survival did not differ between HIT-positive and HIT-negative cohorts (78% and 79%, respectively). CONCLUSION: Heparin-induced thrombocytopenia is a frequent complication among patients hospitalized for heart failure who are awaiting heart transplantation. Timely HIT-antibody screening and the use of alternative forms of systemic anti-coagulation may permit successful transplantation with intermediate survival rates comparable to those of HIT-negative recipients.