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Dive into the research topics where Lawrence J. Sinak is active.

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Mayo Clinic Proceedings | 2002

Consecutive 1127 Therapeutic Echocardiographically Guided Pericardiocenteses: Clinical Profile, Practice Patterns, and Outcomes Spanning 21 Years

Teresa S.M. Tsang; Maurice Enriquez-Sarano; William K. Freeman; Marion E. Barnes; Lawrence J. Sinak; Bernard J. Gersh; Kent R. Bailey; James B. Seward

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.


Circulation | 2005

Clinical Presentation, Investigation, and Management of Pulmonary Vein Stenosis Complicating Ablation for Atrial Fibrillation

Douglas L. Packer; Paul C. Keelan; Thomas M. Munger; Jerome F. Breen; Sam Asirvatham; Laura A. Peterson; Kristi H. Monahan; Mary F. Hauser; Krishnaswamy Chandrasekaran; Lawrence J. Sinak; David R. Holmes

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≤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≤0.001) and a residual gradient of 3±4 mm Hg (P≤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.


American Journal of Cardiology | 1990

Transesophageal echocardiography in critically III patients

Jae K. Oh; James B. Seward; Bijoy K. Khandheria; Bernard J. Gersh; Christopher G.A. McGregor; William K. Freeman; Lawrence J. Sinak; A. Jamil Tajik

The feasibility, safety and clinical impact of transesophageal echocardiography were evaluated in 51 critically ill intensive care unit patients (28 men and 23 women; mean age 63 years) in whom transthoracic echocardiography was inadequate. At the time of transesophageal echocardiography, 30 patients (59%) were being mechanically ventilated. Transesophageal echocardiography was performed without significant complications in 49 patients (96%), and 2 patients with heart failure had worsening of hemodynamic and respiratory difficulties after insertion of the transesophageal probe. The most frequent indication, in 25 patients (49%), was unexplained hemodynamic instability. Other indications included evaluation of mitral regurgitation severity, prosthetic valvular dysfunction, endocarditis, aortic dissection and potential donor heart. In 30 patients (59%), transesophageal echocardiography identified cardiovascular problems that could not be clearly diagnosed by transthoracic echocardiography. In the remaining patients, transesophageal echocardiography permitted confident exclusion of suspected abnormalities because of its superior imaging qualities. Cardiac surgery was prompted by transesophageal echocardiographic findings in 12 patients (24%) and these findings were confirmed at operation in all. Therefore, transesophageal echocardiography can be safely performed and has a definite role in the diagnosis and expeditious management of critically ill cardiovascular patients.


Mayo Clinic Proceedings | 2010

Pericardial Disease: Diagnosis and Management

Masud H. Khandaker; Raul E. Espinosa; Rick A. Nishimura; Lawrence J. Sinak; Sharonne N. Hayes; Rowlens M. Melduni; Jae K. Oh

Pericardial diseases can present clinically as acute pericarditis, pericardial effusion, cardiac tamponade, and constrictive pericarditis. Patients can subsequently develop chronic or recurrent pericarditis. Structural abnormalities including congenitally absent pericardium and pericardial cysts are usually asymptomatic and are uncommon. Clinicians are often faced with several diagnostic and management questions relating to the various pericardial syndromes: What are the diagnostic criteria for the vast array of pericardial diseases? Which diagnostic tools should be used? Who requires hospitalization and who can be treated as an outpatient? Which medical management strategies have the best evidence base? When should corticosteroids be used? When should surgical pericardiectomy be considered? To identify relevant literature, we searched PubMed and MEDLINE using the keywords diagnosis, treatment, management, acute pericarditis, relapsing or recurrent pericarditis, pericardial effusion, cardiac tamponade, constrictive pericarditis, and restrictive cardiomyopathy. Studies were selected on the basis of clinical relevance and the impact on clinical practice. This review represents the currently available evidence and the experiences from the pericardial clinic at our institution to help guide the clinician in answering difficult diagnostic and management questions on pericardial diseases.


Mayo Clinic Proceedings | 2000

Outcomes of Primary and Secondary Treatment of Pericardial Effusion in Patients With Malignancy

Teresa S.M. Tsang; James B. Seward; Marion E. Barnes; Kent R. Bailey; Lawrence J. Sinak; Lynn H. Urban; Sharonne N. Hayes

OBJECTIVE To evaluate the treatment strategies for primary and secondary management of malignancy-related pericardial effusions. PATIENTS AND METHODS Retrospective review of Mayo Clinic Rochester charts and external records of patients with pericardial effusion associated with malignant disease who required treatment between February 1979 and June 1998 was performed. Telephone interviews with patients, their families, or their physicians were conducted to determine the outcomes of treatment. Recurrence of pericardial effusion and survival were the main outcome measures. RESULTS Of 1002 consecutive pericardiocenteses performed during the period under study, 341 were performed in 275 patients with confirmed malignant disease. Patients were followed up for a minimum of 190 days, unless death occurred first. Of 275 patients, recurrence of pericardial effusion or persistent drainage necessitated secondary management in 59 (43 of 118 simple pericardiocenteses, 16 of 139 pericardiocenteses with extended catheter drainage, and 0 of 18 pericardial surgery following temporizing pericardiocentesis). Recurrence was strongly and independently predicted by absence of pericardial catheter for extended drainage, large effusion size, and emergency procedures. Recurrence after secondary management occurred in 12 patients: 11 underwent successful pericardiocentesis with extended catheter drainage, and 1 had pericardial surgery. Median survival of the cohort was 135 days, and 26% survived the first year after diagnosis of pericardial effusion. Male sex, positive fluid cytology for malignant cells, lung cancer, and clinical presentation of tamponade or hemodynamic collapse were independently associated with poor survival. CONCLUSION Echocardiographically guided pericardiocentesis with extended catheter drainage appears to be safe and effective for both primary and secondary management of pericardial effusion in patients with malignancy.


Mayo Clinic Proceedings | 1999

Dynamic Left Ventricular Outflow Tract Obstruction in Acute Coronary Syndromes: An Important Cause of New Systolic Murmur and Cardiogenic Shock

John H. Haley; Lawrence J. Sinak; A. Jamil Tajik; Steve R. Ommen; Jae K. Oh

Dynamic left ventricular outflow tract (LVOT) obstruction has traditionally been associated with hypertrophic obstructive cardiomyopathy. Recently, acute dynamic LVOT obstruction has been described as a complication of myocardial infarction (MI). Herein the cases of 3 patients are described, all of whom presented with a systolic murmur and electrocardiographic evidence of MI. All 3 patients developed cardiogenic shock and were subsequently found by echocardiography to manifest an acute dynamic LVOT obstruction. Cardiogenic shock persisted until therapy was directed toward decreasing the degree of the dynamic LVOT obstruction. The treatment of acute coronary syndromes in the presence of a dynamic LVOT obstruction differs from the traditional treatment of acute coronary syndromes and includes the use of s-blockers and α,-agonists, as well as the avoidance of therapies that aggravate the magnitude of the LVOT obstructive gradient, including nitrates, inotropic agents, and afterload reduction. The development of a systolic murmur in the setting of acute MI complicated by cardiogenic shock with only a small elevation in creatine kinase suggests the presence of a dynamic LVOT obstruction, as well as the classical mechanical complications of MI, namely, ventricular septal rupture and papillary muscle rupture. The presence of a dynamic LVOT obstruction is reliably detected by transthoracic echocardiography or by transesophageal echocardiography if transthoracic image quality is sub-optimal.


Circulation | 1991

Value and limitations of transesophageal echocardiography in assessment of mitral valve prostheses.

Buoy K. Khandheria; James B. Seward; Jae Oh; William K. Freeman; B. A. Nichols; Lawrence J. Sinak; Fletcher A. Miller; Abdul J. Tajik

BackgroundTransthoracic Doppler echocardiography examination has become an integral part of the investigations performed in patients with mitral valve prostheses. The limitations of the transthoracic approach are well documented. Transesophageal echocardiography provides a unique window for achieving a clear view of the mitral prosthesis. Methods and ResultsThis study shows the usefulness of transesophageal echocardiography in clinical practice for assessment of patients with a mitral valve prosthesis. This technique demonstrated an abnormality in 48% of patients who had normal results on transthoracic examination. The overall sensitivity of transesophageal echocardiography was 96%. ConclusionsTransesophageal echocardiography constitutes an essential part of a comprehensive two-dimensional/Doppler echocardiographic examination in patients with suspected malfunction of mitral prostheses. (Circulation 1991;83:1956—1968)


Proceedings of the IEEE | 1983

High-speed three-dimensional X-ray computed tomography: The dynamic spatial reconstructor

Richard A. Robb; Eric A. Hoffman; Lawrence J. Sinak; L.D. Harris; Erik L. Ritman

Most X-ray CT scanners require a few seconds to produce a single two-dimensional (2-D) image of a cross section of the body. The accuracy of full three-dimensional (3-D) images of the body synthesized from a contiguous set of 2-D images produced by sequential CT scanning of adjacent body slices is limited by 1) slice-to-slice registration (positioning of patient); 2) slice thickness; and 3) motion, both voluntary and involuntary, which occurs during the total time required to scan all slices. Therefore, this method is inadequate for true dynamic 3-D imaging of moving organs like the heart, lungs, and circulation. To circumvent these problems, the Dynamic Spatial Reconstructor (DSR) was designed by the Biodynamics Research Unit at the Mayo Clinic to provide synchronous volume imaging, that is stop-action (1/100 s), high-repetition rate (up to 60/s), simultaneous scanning of many parallel thin cross sections (up to 240, each 0.45 mm thick, 0.9 mm apart) spanning the entire anatomic extent of the bodily organ(s)of interest. These capabilities are achieved by using multiple X-ray sources and multiple 2-D fluoroscopic video camera assemblies on a continually rotating gantry. Desired tradeoffs between temporal, spatial, and density resolution can be achieved by retrospective selection and processing of appropriate subsets of the total data recorded during a continuous DSR scan sequence.


Circulation | 1995

Changes in Effective Regurgitant Orifice Throughout Systole in Patients With Mitral Valve Prolapse A Clinical Study Using the Proximal Isovelocity Surface Area Method

Maurice Enriquez-Sarano; Lawrence J. Sinak; Abdul J. Tajik; Kent R. Bailey; J B Seward

BACKGROUND In patients with mitral valve prolapse, spontaneous changes of the effective regurgitant orifice during systole are not well documented. Such changes can now be analyzed by use of the proximal isovelocity surface area method, but the changes raise concern about the reliability of this method for assessing overall severity of regurgitation in these patients. METHODS AND RESULTS In a prospective study of 42 patients with mitral valve prolapse, the effective mitral regurgitant orifice was calculated at four phases of systole (early, mid, mid-late, and late) as the ratio of regurgitant flow to regurgitant velocity by use of the proximal isovelocity surface area method. Throughout systole, the effective regurgitant orifice increased significantly, from 32 +/- 27 mm2 in early systole to 41 +/- 27 in midsystole, 55 +/- 30 in mid-late systole, and 107 +/- 66 mm2 during late systole (P < .0001). Phasic regurgitant volume increased from early to mid-late systole but decreased in late systole. For quantitation of the overall effective regurgitant orifice, four approaches using the proximal isovelocity surface area were compared with simultaneously performed quantitative Doppler echocardiography (54 +/- 30 mm2) and quantitative two-dimensional echocardiography (51 +/- 29 mm2). All correlations were good (r > .95), but overestimation was considerable when the largest flow convergence was used (70 +/- 39 mm2; both P < .0001), significant when the simple mean of the four phases was used (59 +/- 36 mm2; P = .005 and P = .0007, respectively), mild when a weighted mean of the four phases was used (55 +/- 33 mm2; P = .41 and P = .01, respectively), and no overestimation was observed when the effective regurgitant orifice calculated at maximum regurgitant velocity was used (54 +/- 30 mm2; P = .29 and P = .17, respectively). CONCLUSIONS Phasic changes of mitral regurgitation are observed in patients with mitral valve prolapse. The effective regurgitant orifice increases throughout systole. Regurgitant volume also increases initially but tends to decrease in late systole. These changes can lead to overestimation of the overall degree of regurgitation, but properly timed measurements made by use of the proximal isovelocity surface area method allow an accurate estimation of the overall effective regurgitant orifice.


Journal of The American Society of Echocardiography | 1989

Aortic dissection: review of value and limitations of two-dimensional echocardiography in a six-year experience.

Bijoy K. Khandheria; A. Jamil Tajik; Catherine L. Taylor; Robert E. Safford; Fletcher A. Miller; Anthony W. Stanson; Lawrence J. Sinak; Jae K. Oh; James B. Seward

The utility of transthoracic two-dimensional echocardiography in patients with aortic dissection was assessed by retrospective analysis in 67 patients: 31 patients with DeBakey type I, 21 patients with type II, 10 patients with type III, and five patients with false-positive diagnoses. Aortic dissection was correctly identified by two-dimensional echocardiography in 49 patients; 13 had false-negative diagnoses. Therefore the sensitivity was 79%, and the positive predictive accuracy was 91%. Transthoracic two-dimensional echocardiography is a reasonable screening technique for diagnosis of aortic dissection.

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A. Jamil Tajik

University of Wisconsin-Madison

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Bijoy K. Khandheria

University of Wisconsin-Madison

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