Publications by authors named "Osama T Siddiqui"

Objective: The standard right atrial lesion (RAL) set, as originally outlined in the Cox-Maze III procedure, can be technically challenging when using a cryoprobe to create the lesions. We report our initial experience with an alternative set of RALs for the surgical treatment of atrial fibrillation (AF).

Methods: Between September 2011 and January 2015, a total of 112 patients underwent a CryoMaze procedure with biatrial lesions using argon-based cryoablation (cryoprobe temperature, -160°C).

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Limited therapies exist for patients with congenital heart disease (CHD) who develop right ventricular (RV) dysfunction. Bone marrow-derived mesenchymal stem cells (MSCs) have not been evaluated in a preclinical model of pressure overload, which simulates the pathophysiology relevant to many forms of CHD. A neonatal swine model of RV pressure overload was utilized to test the hypothesis that MSCs preserve RV function and attenuate ventricular remodeling.

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Stem cell therapy has the optimistic goal of regenerating the myocardium as defined by re-growth of lost or destroyed myocardium. As applied to patients with heart failure, many confuse or limit the regenerative definition to just improving myocardial function and/or decreasing myocardial scar formation, which may not be the most important clinical outcome to achieve in this promising field of molecular medicine. Many different stem cell-based therapies have been tested and have demonstrated a safe and feasible profile in adult patients with heart failure, but with varied efficacious end points reported.

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Background: We sought to determine the location, expression, and characterization of cardiac stem cells (CSCs) in children with end-stage heart failure (ESHF). We hypothesized ESHF myocardium would contain an increased number of CSCs relative to age-matched healthy myocardium, and ESHF-derived CSCs would have diminished functional capacity as evidenced by reduced telomere length.

Methods: Tissue samples were obtained from the explanted hearts of children undergoing heart transplantation with ESHF, defined as New York Heart Association class III or IV and ejection fraction less than 0.

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We have demonstrated that human neonatal cardiosphere-derived cells (CDCs) derived from the young are more regenerative due to their robust secretome. However, it is unclear how the decompensated pediatric heart impacts the functional activity of their CDCs. Our aim was to characterize the potency of pediatric CDCs derived from normal functioning myocardium of control heart disease (CHD) patients to those generated from age-matched end stage heart failure (ESHF) patients and to determine the mechanisms involved.

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Aims: The detrimental effects of inflammation following cardiopulmonary bypass (CPB) could negatively affect the postoperative outcome in a specific subset of high-risk patients. We therefore investigated the impact of a CPB circuit (Admiral, Eurosets, Italy) that allows separation of intracavitary and mediastinal blood on the release of biochemical markers and clinical outcome when compared with a conventional circuit.

Methods: Thirty patients undergoing aortic valve surgery were prospectively enrolled and assigned to Admiral group (Group 1, G1, n = 15) or conventional CPB group (Group 2, G2, n = 15).

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Complete atrio-ventricular septal defects (CAVSD) are present in about 3% of children born with congenital heart pathologies. They usually require early surgical correction, mostly in infancy, and surgery is considered to be the gold standard. It is unlikely that anyone would survive beyond the first years without severe morbidity.

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Objectives: Adequate knowledge and positive attitudes of health care professionals regarding deceased-donor organ transplants lead to higher donation consent rates. This study assessed the knowledge and attitudes of health care professionals toward this issue in the light of recent organ transplant legislation in Pakistan.

Materials And Methods: Health care professionals in critical care areas of 2 hospitals in Karachi were selected (n=243) and asked to complete a questionnaire regarding their knowledge and attitudes toward deceased-donor organ transplants.

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Background: Risk assessment prior to long-term ventricular assist device (VAD) placement has been shown to be crucial for successful outcomes and efficient resource utilization. Short-term VADs are often used as salvage therapy in acute heart failure when the clinical scenario precludes such thorough preoperative assessment. Our goal was to devise a risk stratification system that may be used shortly after stabilization of hemodynamics with a short-term VAD to predict the likelihood of survival.

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