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S B Labib

Publications and source records attributed to S B Labib.

8 recordsLinked to original sources
PubMed1999

Intimal tear without hematoma: an important variant of aortic dissection that can elude current imaging techniques.

BACKGROUND: The modern imaging techniques of transesophageal echocardiography, CT, and MRI are reported to have up to 100% sensitivity in detecting the classic class of aortic dissection; however, anecdotal reports of patient deaths from a missed diagnosis of subtle classes of variants are increasingly being noted. METHODS AND RESULTS: In a series of 181 consecutive patients who had ascending or aortic arch repairs, 9 patients (5%) had subtle aortic dissection not diagnosed preoperatively. All preoperative studies in patients with missed aortic dissection were reviewed in detail. All 9 patients (2 with Marfan syndrome, 1 with Takayasu's disease) with undiagnosed aortic dissection had undergone >/=3 imaging techniques, with the finding of ascending aortic dilatation (4.7 to 9 cm) in all 9 and significant aortic valve regurgitation in 7. In 6 patients, an eccentric ascending aortic bulge was present but not diagnostic of aortic dissection on aortography. At operation, aortic dissection tears were limited in extent and involved the intima without extensive undermining of the intima or an intimal "flap." Eight had composite valve grafts inserted, and all survived. Of the larger series of 181 patients, 98% (179 of 181) were 30-day survivors. CONCLUSIONS: In patients with suspected aortic dissection not proven by modern noninvasive imaging techniques, further study should be performed, including multiple views of the ascending aorta by aortography. If patients have an ascending aneurysm, particularly if eccentric on aortography and associated with aortic valve regurgitation, an urgent surgical repair should be considered, with excellent results expected.

Adult↗
PubMed1995

Cardiac papillary fibroelastoma.

Papillary fibroelastomas are rare cardiac tumors, but they are the most common primary tumor of the heart valves. These lesions occur on any of the valves or endothelial surfaces of the heart and may be detected by echocardiography, cardiac catheterization, during open heart operation for other conditions, or at autopsy. Because of their potential for cerebral and coronary embolization, even small papillary fibroelastomas should be excised.

Aged↗
PubMed1995

Etiology and management of chronic valve disease in antiphospholipid antibody syndrome and systemic lupus erythematosus.

Unlike the Libman-Sacks vegetations of acute systemic lupus erythematosus (SLE), which are usually asymptomatic, valve involvement in chronic SLE and primary antiphospholipid antibody syndrome (APLAS) is similar to that of chronic rheumatic disease. Typical findings include valve thickening and nodularity, poor coaptation, and regurgitation. Elevated levels of antiphospholipid antibodies have been associated with the development of these valvular abnormalities in some but not all reported cases, and there are undoubtedly other etiologic cofactors. When cardiac valvular replacement is required, special attention must be given to preoperative reduction of elevated antibody levels, prevention of intraoperative thromboembolism, and prompt and aggressive postoperative anticoagulation.

Adult↗
PubMed1994

Aortic dissection and aortic aneurysm surgery.

During the last year, the role of noninvasive studies for aortic dissection--magnetic resonance imaging, computed tomography scanning, and transesophageal echocardiography--has become better defined. Both magnetic resonance imaging and transesophageal echocardiography are highly accurate in detecting aortic dissection. On transesophageal echocardiographic imaging of the ascending aorta, artifacts may be present that mimic an intimal flap (septum). These linear echo densities have characteristic features which distinguish them from a true intimal flap (septum). Their recognition is critical in avoiding false positive transesophageal echocardiography findings. The general consensus on operations for ascending aorta and aortic arch dissection is that patients should be operated upon immediately. Controversy still remains, however, as to whether the aortic arch needs replacement at the time of the ascending and proximal aortic arch repair. Most authors agree that deep hypothermia with circulatory arrest is the preferable technique for acute aortic dissection repair and for surgery on the aortic arch in adults. Retrograde perfusion of the jugular veins is an added advantage. For acute aortic dissection involving the descending thoracic or thoracoabdominal aorta, evidence continues to accumulate that initial medical therapy with beta-blockers and antihypertensives is the preferable mode of treatment unless complications requiring surgery arise. Percutaneous techniques are increasingly being described, including fenestration of the aortic dissection septum, stenting of the aorta or aortic branches, and insertion of intraluminal aortic tube grafts. The safety of surgery on the thoracoabdominal aorta and on the descending thoracic aorta, including the prevention of complications, is reviewed.

Adolescent↗
PubMed1992

Myocardial infarction caused by cardiac microvasculopathy in a patient with the primary antiphospholipid syndrome.

Antiphospholipid antibodies occur in various clinical states, including the primary antiphospholipid syndrome. Clinical features in these conditions appear to be caused by vasculopathy associated with the presence of these antibodies. We report the case of a patient with primary antiphospholipid syndrome who experienced cardiac necrosis secondary to myocardial microvasculopathy in the absence of vasculitis. This case demonstrates unequivocally that noninflammatory myocardial microvasculopathy occurs in the primary antiphospholipid syndrome per se without any clinical or immunologic signs of systemic lupus erythematosus or other disease process. The histopathologic findings in the skin and myocardial biopsies showed a noninflammatory vasculopathy characterized by bland thrombi and lack of infiltration of the vessel wall by inflammatory cells. Ultrastructural examination of the myocardial biopsy confirmed the vascular thrombosis and endothelial activation and showed no deposits in basement membranes. The patient survived after appropriate treatment. Evidence presented here supports the concept that the vasculopathy in the antiphospholipid syndrome is distinct from other types of vascular occlusions seen in systemic lupus erythematosus. We suggest that myocardial biopsy can be crucial in showing an underlying myocardial ischemic process despite "normal" findings on coronary angiography. Results of the biopsy hastened the decision to use potentially lifesaving plasmapheresis and anticoagulation therapy in this patient.

Adult↗
PubMed1992

Obstruction of right ventricular outflow tract caused by intracavitary metastatic disease: analysis of 14 cases.

Obstruction of the right ventricular outflow tract from metastatic disease is rare. Eleven previous case reports and three new cases are presented. Two tumor types (pancreas and breast), not previously associated with right ventricular outflow tract obstruction, are included. Congestive symptoms, systolic murmur and right axis deviation or right bundle branch conduction abnormality were universal features. Echocardiography is valuable in the delineation of metastatic cardiac involvement and the detection of intracardiac gradients. Adverse hemodynamic consequences developed in 3 of 10 patients who underwent right heart catheterization in which two died. This procedure should be performed only when absolutely necessary. Metastatic obstruction of the right ventricular outflow tract should be considered in the absence of widespread malignancy because the heart was the sole site of metastasis in 5 of 10 autopsy patients. Two patients with solitary cardiac metastasis benefited from resection of the obstructing tumor, underscoring the importance of early identification of this subgroup.

Adenocarcinoma↗
PubMed1990

Determinants of sensitivity and specificity of electrocardiographic criteria for left ventricular hypertrophy.

Numerous electrocardiographic criteria, which are largely dependent on fixed voltage thresholds, have been proposed for the diagnosis of left ventricular hypertrophy (LVH). Electrocardiographic criteria for LVH were examined in 4,684 subjects of the Framingham Heart Study who underwent echocardiographic study for LVH. Echocardiographic LVH was detected in 290 men (14.2%) and 465 women (17.6%). Electrocardiographic features of LVH were present in 2.9% of men (60/2,042) and 1.5% of women (39/2,642). The overall sensitivity of the electrocardiographic diagnosis of LVH was 6.9%, whereas specificity was 98.8%. Sensitivity of the electrocardiogram (ECG) for LVH was marginally lower in women than in men (5.6% vs. 9.0%, p = 0.075). Obesity was inversely associated with sensitivity (p less than 0.05, both sexes combined, sex-adjusted). Smoking was also inversely related to sensitivity (p = 0.001, both sexes combined, sex-adjusted). In contrast, sensitivity of the ECG increased with age (p less than 0.001, both sexes combined, sex-adjusted). These findings suggest that electrocardiographic detection of LVH can be improved by incorporating information about noncardiac factors that impact on electrocardiographic sensitivity for LVH, presumably by attenuating QRS voltage. New strategies that take into consideration sex, age, smoking status, and obesity might improve the sensitivity of the ECG without diminishing specificity.

Age Factors↗