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Nirav C Patel

Publications and source records attributed to Nirav C Patel.

9 recordsLinked to original sources
PubMed2005

Robotic assisted multivessel minimally invasive direct coronary artery bypass with port-access stabilization and cardiac positioning: paving the way for outpatient coronary surgery?

BACKGROUND: Minimimal access multivessel coronary artery bypass grafting with same day hospital discharge remains the ultimate goal. We evaluated the feasibility for achieving multivessel coronary bypass through minimal access. METHODS: From January to July 2003, 30 patients under went off-pump minimally invasive multivessel coronary bypass. Internal mammary arteries were harvested with robotic telemanipulation with three ports. A 2-inch to 3-inch incision with soft tissue retractor was used to perform coronary anastomosis. Robotic ports were used to introduce stabilization and cardiac positioning devices. Endoscopic harvesting of radial artery was done when necessary. RESULTS: Twenty-three patients (77%) had anterior throracotomy approach and 7 (23%) had transabdominal approach. Average number of bypass grafts was 2.6 (range 2-4). There was no mortality in hospital or on 30-day follow-up. Twenty-nine patients (97%) were extubated on the operating table. Two patients required reoperation for bleeding and 1 of those patients needed conversion to sternotomy for additional bypass grafting. Within 24 hours of surgery 50% of patients (n = 15) were discharged, 10% (n = 3) were discharged in 24 to 36 hours, 17% (n = 5) were discharged in 36 to 48 hours, 17% (n = 5) were discharged in 48 to 72 hours, and 2 patients stayed more than 3 days in the hospital. Two patients needed readmission to hospital within 30 days; 1 for pleural effusion and 1 for wound infection. CONCLUSIONS: Robotic harvesting of internal mammary arteries and port access stabilization and cardiac positioning allows multivessel coronary bypass to be performed through a small incision. Currently, the majority of the patients can be safely discharged within 36 hours of operation.

Aged↗
PubMed2004

First robotic endoscopic epicardial isolation of the pulmonary veins with microwave energy in a patient in chronic atrial fibrillation.

The pulmonary veins have been demonstrated to play an important role in generating atrial fibrillation. We report the first successful endoscopic epicardial isolation of the pulmonary veins in a patient with permanent atrial fibrillation, along with a 1-year follow-up. The procedure consisted of making a conduction block around the pulmonary veins with a flexible microwave energy delivery probe. The probe was placed endoscopically on the left atrial epicardium with the aid of robotic instruments.

Adrenergic beta-Antagonists↗
PubMed2004

Emergency conversion to cardiopulmonary bypass during attempted off-pump revascularization results in increased morbidity and mortality.

OBJECTIVE: We sought to evaluate outcomes and predictors of emergency conversion to cardiopulmonary bypass during attempted off-pump coronary bypass surgery. METHODS: From January 1999 through July 2002, 1678 consecutive isolated coronary artery bypass operations were performed at Lenox Hill Hospital, with the intention to treat all patients with off-pump coronary bypass surgery. Fifty (2.97%) patients required urgent conversion to cardiopulmonary bypass. All the preoperative, intraoperative, and postoperative variables were collected and analyzed in accordance with the New York State Cardiac Surgery Reporting System. Multivariate regression analysis was performed to determine predictors for conversion. RESULTS: In-hospital mortality and major morbidity were significantly lower in the nonconverted group compared with the converted patients (mortality: 1.47% [n = 24] vs 12% [n = 6], P = .001; stroke: 1.1% [n = 18] vs 6% [n = 3], P = .02; renal failure: 1.23% [n = 20] vs 6% [n = 3], P = .02; deep sternal wound infection: 1.54% [n = 25] vs 8% [n = 4], P = .009; respiratory failure: 3.75% [n = 61] vs 28% [n = 14], P < .0001; nonconverted vs converted patients, respectively). The annual incidence of conversion decreased during the study period. There was a significant reduction in the incidence of conversion after routine use of a cardiac positioning device to performing lateral and inferior wall grafts (4.2% [n = 27] vs 2.3% [n = 23], P = .04). None of the preoperative variables were independent predictors of conversion on multivariate regression analysis. CONCLUSIONS: Because emergency conversion to cardiopulmonary bypass during attempted off-pump coronary bypass surgery results in significantly higher morbidity and mortality, studies comparing off-pump coronary bypass surgery with conventional coronary artery surgery should include converted patients in the off-pump group. In our experience, emergency conversion is an unpredictable event. The incidence of conversion decreases with increasing experience of surgeons in performing off-pump coronary surgery and use of a cardiac positioning device.

Adult↗
PubMed2003

Evolving revascularization approaches for myocardial ischemia.

Stable angina pectoris secondary to ischemic heart disease is a common and disabling condition. Medical therapy aims to relieve symptoms, improve exercise capacity, and decrease cardiac events by reducing myocardial oxygen demand or improving coronary blood supply to the ischemic myocardium. If medical treatment is inadequate, invasive revascularization procedures to improve coronary perfusion are considered. Percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft (CABG) surgery are well-established and widely used myocardial revascularization techniques. Recent advances in PTCA have attempted to address the problem of restenosis, initially through the deployment of bare metal intracoronary stents and, more recently, with drug-eluting stents. Developments in CABG have focused on reducing the invasiveness of the procedure and minimizing the incidence of serious complications. Refinements include the use of mechanical stabilizers, endoscopic harvesting of conduit vessels, robotic telemanipulation systems, and fully automated anastomotic devices. Surgical laser transmyocardial revascularization and therapeutic angiogenesis represent newer approaches to coronary revascularization. Therapeutic angiogenesis aims to deliver an angiogenic growth factor or cytokine to the myocardium to stimulate collateral blood vessel growth throughout the ischemic tissue. The angiogenic factor may be administered as a recombinant protein or as a transgene within a plasmid or gene-transfer vector. Ongoing angiogenic gene therapy clinical trials are evaluating which factors, vectors, and delivery techniques hold the greatest promise for management of patients with chronic stable angina.

Angiogenesis Inducing Agents↗
PubMed2003

Off-pump coronary artery bypass surgery does not reduce gastrointestinal complications.

OBJECTIVES: Gastrointestinal (GI) complications following on-pump coronary artery bypass grafting (CABG) are rare, but carry a high mortality rate. Prolonged cardiopulmonary bypass (CPB) has been associated with a higher incidence of such complications. Little is known about the effect of avoiding CPB on GI complications. Our hypothesis was that off-pump CABG might reduce such complications. METHODS: A total of 2327 consecutive cases undergoing isolated CABG between April 1997 and May 2001 were identified from four consultants' practice at the two cardiothoracic centres involved in this study. We performed a multivariable logistic regression analysis to identify the risk factors for development of post-operative GI complications. Potential risk factors considered in the logistic model were age, sex, angina, ejection fraction, peripheral vascular disease, renal dysfunction, redo operations, previous GI complications, priority of surgery and the use of CPB. RESULTS: A total of 1210 cases were performed on CPB, compared to 1117 off-pump. The incidence of GI complications was 1.2% (n = 14) in the on-pump group and 1.6% (n = 18) in the off-pump group (P = 0.347). The incidence of in-hospital mortality, in the patients who had a GI complication, was 28.6% (n = 4) and 22.2% (n = 4), respectively (P = 0.681). The results of the logistic regression analysis showed that renal dysfunction, advancing age and previous history of GI surgery are significant risk factors for GI complications after coronary bypass surgery whether CPB is used or not. CONCLUSIONS: Our study suggests that off-pump and on-pump techniques are similar in the rates of GI complications. We suggest that a properly designed randomized control trial is needed to verify our findings.

Age Factors↗
PubMed2002

Neurological outcomes in coronary surgery: independent effect of avoiding cardiopulmonary bypass.

BACKGROUND: Recent studies examining neuroprotective effects of off-pump coronary artery bypass grafting (CABG) have shown inconsistent results. We examined our database to quantify the independent effects of avoidance of cardiopulmonary bypass (CPB) and aortic manipulation on neurologic outcomes after CABG. METHODS: A total of 2,327 consecutive cases undergoing isolated CABG between April 1997 and May 2001 were identified at our two institutions. Patients were divided into three groups: on CPB, off-pump with aortic manipulation, and off-pump without aortic manipulation. To control for the confounding effects of other risk factors, we performed a multivariate logistic regression analysis. Potential covariates considered in the logistic model included age, sex, redo operations, diabetes, chronic obstructive pulmonary disease, neurologic disease, peripheral vascular disease, ejection fraction, and priority of operation. RESULTS: A total of 1,210 cases were performed on CPB, compared with 520 off-pump with aortic manipulation, and 597 off-pump without aortic manipulation. The incidence of focal neurologic deficit was 1.6% (n = 19) in the on-pump group, 0.4% (n = 2) in the off-pump with aortic manipulation group, and 0.5% (n = 3) for the off-pump without aortic manipulation group (p for trend = 0.027). The results of the multivariate logistic regression analysis demonstrated that use of CPB was a risk factor for focal neurologic deficit, with an odds ratio of 3.82 (95% confidence interval, 1.41 to 10.34; p = 0.005). Aortic manipulation did not significantly influence neurologic outcome in off-pump patients. CONCLUSIONS: Off-pump operation, with or without aortic manipulation, reduces adverse neurologic outcomes compared with on-pump procedures.

Aged↗
PubMed2002

'Shunt shuffle'-a simple technique of introducing intracoronary shunts for off-pump coronary artery bypass.

Intracoronary shunting is a useful method for maintaining distal perfusion as well as providing a bloodless field during off-pump coronary revascularization. Intracoronary shunts require insertion of both ends through a limited arteriotomy, which sometimes can be troublesome. We describe the 'shunt shuffle' as a simple technique, which allows rapid, atraumatic and easy insertion of intracoronary shunts.

Catheterization↗
PubMed2002

Does off-pump total arterial revascularization without aortic manipulation influence neurological outcome? A study of 226 consecutive, unselected cases.

BACKGROUND: Off-pump coronary artery bypass (OPCAB) is increasingly reported to have better post-operative outcomes than on-pump coronary artery bypass (ONCAB). Most series report OPCAB in selected cases and therefore the results of such studies are affected by selection bias. We report our series of consecutive, unselected OPCAB cases representing an entire coronary revascularization practice and its effect on neurological outcome. METHODS: Between January and December 2000, 226 consecutive OPCAB cases were performed. These were compared with 258 consecutive ONCAB cases performed by same surgeons historically. There were no significant differences in major demographic characteristics between the two groups. Postoperative outcomes including operation time, ventilation time, inotrope requirement, focal strokes, peak CKMB, length of hospital stay and mortality formed the basis of this study. All OPCAB patients had a median sternotomy approach. Left and right internal mammary arteries and radial arteries were used in varying combinations using composite and sequential grafting techniques to achieve revascularization and completely avoid aortic manipulation. ONCAB cases were performed employing conventional cardiopulmonary bypass techniques and using the left internal mammary artery and saphenous vein grafts as appropriate. RESULTS: OPCAB cases had significantly lower peak CKMB levels, operative time, length of hospital stay and number of grafts. There was a significantly lower incidence of permanent focal neurological events in OPCAB patients (0.4%, n = 1) compared to the ONCAB group (3.9%, n = 10, p = 0.012). CONCLUSION: This study documents the safety of off pump total arterial revascularization without aortic manipulation as the routine technique for coronary bypass surgery. It also demonstrates a significant reduction in the incidence of focal strokes. We conclude that avoidance of both cardiopulmonary bypass and aortic manipulation are important factors in reducing the occurrence of neurological deficits.

Adult↗