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Tahir Tak

Publications and source records attributed to Tahir Tak.

27 records · Page 2Linked to original sources
PubMed2003

Thrombotic occlusion of Bjork-Shiley prosthetic aortic valve.

Thrombotic occlusion of a prosthetic Bjork-Shiley valve is a potentially fatal complication. We present the case of a male, 62 years of age, diagnosed with thrombotic occlusion of prosthetic Bjork-Shiley aortic valve approximately 17 years post implantation. A brief review of the literature focusing on potential risk factors associated with the development of this condition and currently available diagnostic modalities used for evaluation and treatment are presented.

Aortic Valve↗
PubMed2002

Renal cell carcinoma presenting as right atrial mass.

Approximately 190 new cases of renal cell carcinoma infiltrate into the inferior vena cava and right atrium every year. Echocardiography often plays a major role in establishing the diagnosis and in guiding surgical therapy. This report describes a patient who presented with shortness of breath but had no classic signs or symptoms of renal cell carcinoma other than chronic anemia. Transthoracic two-dimensional echocardiography and transesophageal echocardiography established the diagnosis of a right atrial mass extending from the inferior vena cava that was later discovered to be renal cell carcinoma.

Aged↗
PubMed2002

Second case of infective endocarditis caused by Gemella sanguinis.

BACKGROUND: A 69-year-old man presented with a history of spiking fevers and symptoms of transient expressive aphasia and a left hemispheric cerebrovascular accident. A transthoracic echocardiogram revealed thickened mitral leaflets. A subsequent transesophageal echocardiogram demonstrated vegetations on both mitral leaflets and severe mitral regurgitation by color flow imaging. A gram-positive coccus was isolated from the blood culture of this patient. METHODS: The bacterium was identified by polymerase chain reaction (PCR) amplification of its 16S rRNA gene with the broad range eubacterial primers, FD1 and RD1, followed by sequencing of the PCR product. The obtained sequence was compared to all sequences deposited in GenBank and the ribosomal database project II. A phylogenetic tree was created to determine the relatedness of this bacterium to other bacterial species. RESULTS: The phylogenetic tree created from the 1389 bp 16S rDNA sequence indicated that the endocarditis was due to Gemella sanguinis, a member of the normal oral flora and a rare cause of bacteremia. CONCLUSION: This report describes the second case of endocarditis caused by G. sanguinis. A history of periodontal disease and tooth abscess in this patient suggests that the oropharynx was the probable origin of the Gemella bacteremia. We propose that G. sanguinis should be added to the list of Gemella species that can cause endocarditis.

Aged↗
PubMed2002

An update on the epidemiology, pathogenesis and management of infective endocarditis with emphasis on Staphylococcus aureus.

The incidence of infective endocarditis (IE) is thought to be around 4/100,000 person years in the general population, and 15/100,000 over the age of 50 years. The risk of acquiring IE is higher among patients with valvular heart disease (e.g., rheumatic valves, bicuspid aortic valves, myxomatous degeneration, etc.), congenital heart disease (e.g., coarctation, patent ductus arteriosus, ventricular septal defect, etc.), prosthetic cardiac valves, and among intravenous drug abusers. Staphylococcus aureus is one of the most common infective agents of IE, and most commonly originates from nosocomial sources, e.g., intravenous and arterial catheters, pacemaker leads, and prosthetic valves. Endocarditis caused by S aureus has a mortality rate of approximately 20% to 40%. In up to 40% of patients, IE caused by S aureus is associated with embolic complications. The risk of death increases with the development of complications. The epidemiology and microbiology of S aureus are changing rapidly, and resistance to antibiotics, especially methicillin, is becoming more widespread. In this review we will focus on the epidemiology, microbiology, and pathogenesis of S aureus IE, and also summarize the current guidelines for diagnosis, treatment, and prophylaxis of this clinical condition.

Anti-Bacterial Agents↗
PubMed1996

Severity of Aortic Regurgitation Assessed by Digital Image Processing of Doppler Spectral Recordings.

Visual estimates of the intensity of the regurgitant signal (RS) obtained by continuous-wave (CW) Doppler has been used as an indicator of the severity of aortic regurgitation (AR). This study was designed to test this concept quantitatively using digital image processing methods. Twenty-one patients with AR were studied, 14 of whom had concomitant mitral valve disease. Patients with aortic stenosis were excluded. By angiography, 10 patients had mild (grade 1 or 2), 5 had moderate (grade 3), and 6 severe (grade 4) AR. We digitized three well-defined AR envelopes and calculated the mean pixel intensity (MPI) of the RS and the systolic flow signal (SFS) using an offline computer analysis system developed in our laboratory. To negate the effects of different gain settings, the ratio of RS to SFS (RS/SFS ratio) was compared to angiographic grade of AR. Thus, each patient served as his own control. The mean RS/SFS ratio was 0.54 +/- 0.42 SD (range 0.46-0.59) for mild AR, 0.76 +/- 0.71 SD (range 0.65-0.82) for moderate AR, and 0.84 +/- 0.52 (range 0.77-0.92) for severe AR. This RS/SFS ratio correlated well with angiographic severity of AR (r = 0.9). A ratio of <0.6 identified patients with mild AR and >0.6 correlated with moderate-to-severe AR. We conclude that the ratio of the regurgitant to systolic flow CW Doppler signal is an accurate noninvasive indicator of AR severity. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

Journal Article↗
PubMedDate not supplied

Detection of atypical right atrial myxoma by echocardiography.

Atrial myxomas are the most common primary cardiac tumors. They are commonly found in the atria and are attached to the interatrial septum. We report a case of a right atrial cardiac myxoma in a 47-year-old woman who presented with fatigue, right-sided chest pain, and a syncopal episode. Echocardiography demonstrated an atypical attachment of the myxoma to the free wall of the right atrium. The features of cardiac myxoma and the role of echocardiography in the diagnosis and treatment of cardiac myxomas are also discussed.

Echocardiography, Transesophageal↗