Biomedical subjects

Lawrence J Sinak

Publications and source records attributed to Lawrence J Sinak.

10 recordsLinked to original sources

PubMed2005

Clinical presentation, investigation, and management of pulmonary vein stenosis complicating ablation for atrial fibrillation.

BACKGROUND: Although segmental or circumferential ablation is effective in eliminating pulmonary vein (PV)-mediated atrial fibrillation (AF), this procedure may be complicated by the occurrence of PV stenosis. METHODS AND RESULTS: To establish the clinical presentation, diagnostic manifestations, and interventional management of PV stenosis, 23 patients with stenosis of 34 veins complicating ablation of AF were evaluated. Each patient became symptomatic 103+/-100 days after undergoing ablation. In 8 veins, the ablation producing the PV stenosis was a repeated procedure for continued AF. Nineteen patients presented with dyspnea on exertion, 7 with dyspnea at rest, 9 with cough, and 6 with chest pain. On multirow spiral computed tomography examination, the narrowest lumen of the affected PVs measured 3+/-2 mm compared with 13+/-3 mm at baseline (P< or =0.001). The relative perfusion of affected lung segments on isotope scans was reduced to 4+/-3% of total perfusion compared with 22+/-10% in unaffected segments. At percutaneous intervention, these veins showed 80+/-13% stenosis, with a mean gradient of 12+/-5 mm Hg. This was significantly reduced to a residual stenosis of 9+/-8% (P< or =0.001) and a residual gradient of 3+/-4 mm Hg (P< or =0.001). Twenty veins were treated with balloon dilatation alone, whereas 14 veins were stented with standard 10-mm-diameter bare-metal stents. Although the symptomatic response was nearly immediate and impressive, 14 patients developed in-stent or in-segment restenosis, requiring repeated interventions in 13. CONCLUSIONS: Percutaneous intervention produces rapid and dramatic symptom relief in patients with highly symptomatic PV stenosis after radiofrequency ablation for AF. Nevertheless, alternative treatment methods will be required to decrease recurrent in-stent or in-segment restenosis.

Adult↗

PubMed2005

Left atrial appendage aneurysm.

Aneurysms of the left atrial appendage are exceedingly rare. Patients most commonly present with atrial tachyarrhythmias and thromboembolism. Resection of the aneurysm is usually curative. We present a case report of a 60-year-old female with a long-standing history of atrial arrhythmias found to have a large left atrial appendage aneurysm with additional bi-atrial enlargement and a family history of atrial arrhythmias. The patient was successfully treated with resection of the aneurysm and a Cox-Maze III procedure.

Arrhythmias, Cardiac↗

PubMed2005

Ventricular septal hamartoma mimicking hypertrophic cardiomyopathy in a 41-year-old woman presenting with paroxysmal supraventricular tachycardia.

We report an unusual case of cardiac hamartoma involving the ventricular septum. The patient presented with palpitations and exertional chest pain. Echocardiography indicated a large homogeneous mass occupying the superior two-thirds of the ventricular septum. This report confirms the use of transthoracic echocardiography as a screening tool in the diagnosis and management of an uncommon case of a benign cardiac tumor.

Adult↗

PubMed2005

Hydroxychloroquine-induced cardiotoxicity in a 39-year-old woman with systemic lupus erythematosus and systolic dysfunction.

A 39-year-old woman with a history of systemic lupus erythematosus developed chest pain and conduction abnormalities. An echocardiographic examination revealed systolic dysfunction and ventricular thickening. Because of the unclear nature of her cardiac disease, right ventricular endomyocardial biopsy was performed. Light microscopy showed diffuse myocyte vacuolization without myocarditis, and transmission electron microscopy demonstrated sarcoplasmic myelinoid and curvilinear bodies, diagnostic of hydroxychloroquine toxicity. Among patients with autoimmune connective disorders, cardiac dysfunction may be a result of the disease or occasionally of its treatment. Although the nature of the cardiac disease (myocardial, valvular, or pericardial) can generally be evaluated echocardiographically, endomyocardial biopsy may be indicated to rule out diseases with a specific microscopic appearance, such as myocarditis or hydroxychloroquine cardiotoxicity.

Cardiomyopathies↗

PubMed2005

Incidence and predictors of cardiac perforation after permanent pacemaker placement.

BACKGROUND: Pericardial effusion, a sign of cardiac perforation, may complicate permanent pacemaker placement. Risk factors for development of post-permanent pacemaker effusion have not been evaluated. OBJECTIVES: The purpose of this study was to determine the predictors of symptomatic pericardial effusion after permanent pacemaker placement. METHODS: The Mayo Clinic pacemaker and echocardiogram databases were cross-referenced. From 1995 to 2003, 4,280 permanent pacemakers were implanted. Fifty (1.2%) patients developed significant effusion and symptoms consistent with perforation. They were randomly matched with 100 patients without effusion after permanent pacemaker placement. RESULTS: The strongest predictors of postimplant effusion by univariate analysis were the concomitant use of a temporary transvenous pacemaker (hazard ratio [HR] 3.2, 95% confidence interval [CI] 1.6-6.2, P = .001) or steroid use within 7 days prior to implant (HR 4.1, 95% CI 1.1-10, P = .003). Weaker predictors were use of helical screw ventricular leads, body mass index (BMI) <20, older age, and longer fluoroscopy times. Variables associated with lower risk of perforation were right ventricular systolic pressure >35 mmHg (HR 0.70, 95% CI 0.44-0.97, P = .01) or BMI >30 (HR 0.62, 95% CI 0.41-0.93, P = .01). Multivariate predictors were use of temporary pacemaker (HR 2.7, 95% CI 1.4-3.9, P = .01), helical screw leads (HR 2.5; 95% CI 1.4-3.8, P = .04), and steroids (HR 3.2, 95% CI 1.1-5.4, P = .04). Right ventricular systolic pressure >35 mmHg was the only protective factor (HR 0.70, 95% CI 0.50-0.92, P = .02). CONCLUSION: The incidence of postimplant effusions is low. In order to minimize periprocedural permanent pacemaker effusions, temporary pacemaker placement should be avoided unless essential, and particular care should be taken when placing a permanent pacemaker in patients who are taking steroids.

Adult↗

PubMed2005

Outcomes after cardiac perforation during radiofrequency ablation of the atrium.

BACKGROUND: Perforation during catheter procedures in either the atrium or ventricle is relatively uncommon, but potentially fatal if tamponade ensues. This study analyzes the occurrence and outcomes of cardiac perforation during catheter-based radiofrequency ablation procedures in the left atrium. METHODS: All patients with a periprocedure perforation who have undergone radiofrequency ablation for atrial fibrillation (AF) or tachycardia were included. RESULTS: Of 632 procedures performed from January 1999 to October 2004, 15 (2.4%) were complicated by perforation requiring pericardiocentesis. The perforation site was left atrium in 9 (60.0%), right atrium in 1 (6.7%), and right ventricle in 5 (33.3%). Intracardiac echocardiography was used in 13 (86.7%) and revealed an effusion before overt instability in 11 (73.3%). Thirteen (86.7%) patients developed a blood pressure <60 mmHg. The pressure stabilized in all patients after pericardiocentesis (hypotension to intervention: 10.1 +/- 5.1 minutes). The total blood volume removed was 848 +/- 880 mL (left atrium/right atrium: 1,074 +/- 1,002 vs right ventricle: 396 +/- 266, P = 0.168). Two patients required surgery to close left atrium dome perforations. The ablation was completed in 7 (46.7%) patients. Ten (66.7%) later developed early reoccurrence of AF. All patients were neurologically intact at hospital discharge. During a 1.5 +/- 1.1 year follow-up, AF was eliminated (n = 4) or controlled (n = 1) in 5 (71.4%) patients with complete procedures, and 2 (20.0%) patients underwent successful repeat ablation. CONCLUSION: The incidence of perforation during ablation of the left atrium is low. Most perforations occur in the left atrium; however, few require surgical closure. Although less than with uncomplicated procedures, the majority of patients with complete ablations achieve long-term elimination of AF.

Adult↗

PubMed2005

Quantitation of regional ejection fractions using gated tomographic imaging with 99mTc-sestamibi.

BACKGROUND: Gated single photon emission CT (SPECT) sestamibi imaging allows the simultaneous assessment of myocardial perfusion and left ventricular function. OBJECTIVE: The purpose of this study was to evaluate a technique for quantitative regional wall motion assessment using gated SPECT (99m)Tc-sestamibi imaging. PATIENTS AND INTERVENTIONS: Fourteen subjects without cardiac pathology and 25 patients who had experienced myocardial infarction (MI) were studied. After tomographic reconstruction of gated short-axis slices, the identification of endocardial borders was made using a standard edge-detection program in systole and diastole in each of five selected slices. Regional ejection fraction (EF) and myocardial perfusion were determined for five regions within each slice. Ten patients underwent echocardiographic regional wall-motion analysis, the results of which were compared to corresponding regional EF results. RESULTS: High interobserver reproducibility in the assessment of regional EFs was found, with r values ranging from 0.94 to 0.98. In patients with anterior and inferior MIs, the regional EFs were abnormal in the anterior and septal regions, and the inferior and lateral regions, respectively. The regional EFs correlated significantly with regional perfusion in the anterior walls (r = 0.71; p = 0.0001), the lateral walls (r = 0.66; p = 0.0001), and inferior walls (r = 0.54; p = 0.0004). There was a significant association between the regional EFs and the echocardiographic regional wall motion assessment at the base (p < 0.0001), mid-ventricle (p = 0.0004), and apex (p = 0.0003). CONCLUSIONS: Gated SPECT images obtained (99m)Tc-sestamibi can provide reproducible quantitative, segmental regional EFs for multiple left ventricular slices that are significantly associated with subjective regional wall motion assessment by echocardiography.

Adult↗

PubMed2003

Hand-carried ultrasound-guided pericardiocentesis and thoracentesis.

To date, ultrasound-guided centeses have required the use of large, diagnostic ultrasound equipment that can be cumbersome and not readily available. In this study, we sought to evaluate the use of portable, hand-carried ultrasound devices in guidance of pericardiocentesis and thoracentesis. Hand-carried ultrasound was used to define location of the maximal extent of the effusion and its proximity to the skin surface, confirm needle entry and site, and to evaluate postprocedural result. A total of 12 patients who were stable and hospitalized were prospectively enrolled, 9 for pericardiocentesis and 3 for thoracentesis. We concluded that under the direction of a suitably trained physician, hand-carried ultrasound provided images suitable for guidance of a pericardiocentesis or thoracentesis preprocedurally, intraprocedurally, and postprocedurally.

Adolescent↗

PubMed2002

Intracardiac phased-array imaging: methods and initial clinical experience with high resolution, under blood visualization: initial experience with intracardiac phased-array ultrasound.

OBJECTIVES: This study was designed to test the feasibility of high-resolution phased-array intracardiac imaging. BACKGROUND: Intracardiac echocardiographic imaging of the heart during interventional electrophysiologic (EP) procedures has been limited by inadequate ultrasound penetration and absence of Doppler hemodynamic and flow information produced by rotating mechanical ultrasound elements. METHODS: A 10F (3.2 mm) phased-array, variable 5.5 to 10 MHz frequency imaging catheter with a four-way deflectable tip was applied in 24 patients undergoing EP studies. Sixteen prespecified cardiac targets were imaged from a right heart venue. RESULTS: Fifteen patients had no underlying organic heart disease; nine had ischemic, cardiomyopathic, valvular or congenital heart disorders. Longitudinal and short-axis imaging readily disclosed each cardiac valve, support structures and chamber, as well as the pericardium, right and left atrial appendages, the junction of the right atrium and superior vena cava, crista terminalis, tricuspid valve isthmus, coronary sinus orifice, membranous fossa ovalis and pulmonary veins. The average target depth was 8.8+/-1.5 cm (range 0.5 to 15 cm), with adequate penetration at a 7.5 MHz imaging frequency. Color flow and Doppler utilities clearly characterized transaortic and pulmonic valve and pulmonary vein blood flow, including during low output states. CONCLUSIONS: These first human studies with this technology demonstrate the methods, feasibility and utility of intracardiac phased-array vector and Doppler imaging for long-axis, apex-to-base global cardiac imaging. High resolution of endocardial structures and catheters suggests additional utility for visualizing interventional procedures from the right heart.

Arrhythmias, Cardiac↗

PubMed2002

Consecutive 1127 therapeutic echocardiographically guided pericardiocenteses: clinical profile, practice patterns, and outcomes spanning 21 years.

OBJECTIVES: To evaluate consecutive therapeutic echocardiographically (echo)-guided pericardiocenteses performed at Mayo Clinic, Rochester, Minn, from 1979 to 2000 and to determine whether patient profiles, practice patterns, and outcomes have changed over time. PATIENTS AND METHODS: Consecutive echo-guided pericardiocenteses performed between February 1, 1979, and January 31, 2000, for treatment of clinically significant pericardial effusions were identified in the Mayo Clinic Echocardiographic-guided Pericardiocentesis Registry. The medical records of these patients were examined, and a follow-up survey was conducted. Clinical profiles, echocardiographic findings, procedural details, and outcomes were determined for 3 periods: February 1, 1979, through January 31, 1986; February 1, 1986, through January 31, 1993; and February 1, 1993, through January 31, 2000. RESULTS: During the 21-year study period, 1127 therapeutic echo-guided pericardiocenteses were performed in 977 patients. The mean +/- SD age at pericardiocentesis increased from 49+/-14 years in period 1 to 57+/-14 years in period 3. In recent years, cardiothoracic surgery replaced malignancy as the leading cause of an effusion requiring pericardiocentesis and together with malignancy and perforation from catheter-based procedures accounted for nearly 70% of all pericardiocenteses performed. The procedural success rate was 97% overall, with a total complication rate of 4.7% (major, 1.2%; minor, 3.5%). These rates did not change significantly over time. The use of a pericardial catheter for extended drainage increased from 23% in period 1 to 75% in period 3 (P<.001), whereas rates of effusion recurrence and pericardial surgery decreased significantly (P<.001). CONCLUSIONS: The profile of patients presenting with clinically significant pericardial effusion has changed over time. Increasing numbers of older patients and those who have undergone cardiothoracic surgery or catheter-based procedures develop effusions that can be rapidly, safely, and effectively managed with echo-guided pericardiocentesis. Extended drainage with use of a pericardial catheter has become standard practice, and concomitantly, recurrence rates and need for surgical management have decreased considerably.

Age Distribution↗