Biomedical subjects

Naresh Trehan

Publications and source records attributed to Naresh Trehan.

At least 37 records · Page 2Linked to original sources

PubMed2003

Ventilator-associated pneumonia: Incidence, risk factors, outcome, and microbiology.

OBJECTIVE: To determine the incidence, risk factors, outcome, and pathogens of ventilator-associated pneumonia (VAP) in a cardiac surgical intensive care unit (ICU). DESIGN: Prospective study. SETTING: Escorts Heart Institute and Research Centre, New Delhi, India. PARTICIPANTS: Nine hundred fifty-two consecutive patients undergoing cardiac operations who received intermittent positive-pressure ventilation (IPPV). INTERVENTIONS: All patients were assigned into VAP (n = 25) and non-VAP (n = 927) groups. MEASUREMENTS AND MAIN RESULTS: Risk factors and other variables were analyzed with univariate and multivariate analysis. Of the 952 patients studied, 25 (2.6%) had VAP. On univariate analysis, significant risk factors were emergency surgery, chronic obstructive pulmonary disease (COPD), reintubation, coma, steroid treatment, intra-aortic balloon counterpulsation (IABC), enteral feedings, tracheostomy, acute physiology, age, and chronic health evaluation (APACHE II) score, prior antibiotics, and IPPV hours. On multivariate analysis, IPPV hours (153.75 +/- 114.44 v 19.65 +/- 7.99; p < 0.001) and steroids (20% v 0%; p < 0.001) were independent predictors of VAP. The most common pathogens isolated were Pseudomonas aeruginosa (22), Escherichia coli (10), Klebsiella pneumoniae (4), Staphylococcus species (4), and Acinetobacter species (2). The mortality rate in VAP was 16% as compared with 0.2% in non-VAP cases (p < 0.001). CONCLUSION: These data suggest that by univariate analysis the risk factors for VAP were emergency surgery, COPD, reintubation, coma, steroid treatment, IABC, enteral feedings, tracheostomy, APACHE II score, prior antibiotics, and IPPV hours. On multivariate analysis, only IPPV hours and steroids were independent predictors of VAP. Pseudomonas aeruginosa is the most common pathogen associated with VAP, and the mortality is increased with VAP.

Cardiac Surgical Procedures↗

PubMed2003

Multimodality targeted approach in redo off-pump coronary artery bypass surgery.

Records of 86 patients who underwent off-pump redo coronary revascularization between December 1997 and December 2000, were analyzed. Approaches included median sternotomy (47), anterolateral thoracotomy for left anterior descending artery and diagonal targets (35), posterolateral thoracotomy for the obtuse marginal with proximal anastomosis on descending aorta (3), and a combined subxiphoid-anterior thoracotomy approach (1) for right gastroepiploic artery-to-left anterior descending artery anastomosis. The mean age was 61.82 years. There were 2 (2.3%) operative deaths. Complications included perioperative myocardial infarction in 4 patients and reexploration for bleeding in one. Blood transfusion was required in 12 patients. The mean length of hospital stay was 5 +/- 2 days. A multimodality targeted approach for off-pump redo coronary artery bypass offers a less invasive but safer method of myocardial revascularization, with decreased complications, lower blood product requirement, and early hospital discharge.

Aged↗

PubMed2003

Transesophageal echocardiography in hypotensive post-coronary bypass patients.

The utility of transesophageal echocardiography in the evaluation of hypotension in the postoperative period after coronary artery bypass was assessed in 126 patients in the intensive care unit. There were 86 men and 40 women, with a mean age of 58.3 years. The indication for transesophageal echocardiography was hypotension refractory to conventional treatment. Valuable diagnostic information was obtained in 103 patients (82%). Based on the echocardiographic findings, 24 patients (19%) underwent urgent surgical intervention. The mean time required to obtain a diagnosis was 9.6 +/- 2.8 min. No significant complications were noted. Our experience suggests that transesophageal echocardiography is highly specific in diagnosing the cause of postoperative hypotension, thus preventing unnecessary surgical intervention and facilitating decision making in cardiac surgical emergencies.

Cardiac Tamponade↗

PubMed2003

Left ventricular fibroma causing atypical chest pain.

A 29-year-old man with atypical chest pain for 3 years and exertional angina for 3 months was found to have a large homogenous mass in the apicolateral area of the left ventricle. The mass, weighing 78 g, was excised successfully and identified as a fibroma.

Adult↗

PubMed2003

Off-pump surgery: a choice in unstable angina.

The benefit and safety of off-pump coronary artery bypass surgery in patients with unstable angina was assessed retrospectively. From February 1996 to October 2001, 5,306 patients underwent multivessel off-pump coronary artery bypass, of whom 920 (17%) had unstable angina. In these 920 patients, ejection fractions ranged from 15% to 70%, 203 (22%) had an ejection fraction of 20%-35%, and 11 (1%) had an ejection fraction < 20%. Triple-vessel disease was present in 625 patients. Preoperative intraaortic balloon pump support was used in 28 patients. Operative approaches included mid sternotomy (86%), lower partial sternotomy (9%), and left anterior thoracotomy (2%). The number of grafts ranged from 1 to 5 with a mean of 2.43 +/- 0.86, and 92.3% of patients received a left internal mammary artery graft. Twenty-two patients need intraoperative intraaortic balloon pumping. Ten patients (1%) suffered perioperative myocardial infarction. The mean hospital stay was 7.8 +/- 4.3 days. Hospital mortality was 2/920 (0.22%). Intraaortic balloon pumping was helpful in these cases of unstable angina refractory to medical therapy. Off-pump coronary artery surgery was found to be safe and beneficial in these patients.

Adult↗

PubMed2003

Multivessel off-pump coronary artery bypass: analysis of 4953 cases.

BACKGROUND: To avoid the harmful effects of cardiopulmonary bypass (CPB), cardiac surgeons are using off-pump coronary artery bypass (OPCAB) as an effective alternative to conventional coronary artery bypass grafting (CABG). In the present study, we analyze our results with OPCAB in patients with multivessel coronary artery disease and compare them with those achieved in patients who underwent operations on CPB. METHODS: Between January 1997 and April 2002, 4953 patients underwent CABG without CPB (OPCAB group). These patients were compared with 7133 patients who underwent conventional on-pump CABG (CCAB group) during the same period. All patients were operated on through a median sternotomy. The Octopus was used as the mechanical stabilizer, and intracoronary shunts were used in most patients. Transesophageal echocardiography was used in all patients, and epiaortic scanning was used in selected patients. RESULTS: The mean patient age was 59 +/- 8.9 years in the OPCAB group and 57.4 +/- 8.9 years in the CCAB group (P <.001). There were more women in the OPCAB group (11.7% versus 10.4%; P =.023), and 2.8% of the patients required conversion to CPB. The mean numbers of grafts were 3.0 +/- 0.7 and 3.2 +/- 0.8 in the OPCAB and the CCAB groups, respectively (P <.001). More patients in the CCAB group received grafts to the circumflex territory. Intubation times (19 +/- 4 hours versus 25 +/- 6 hours; P <.001), blood losses (350 +/- 41 mL versus 598 +/- 74 mL; P <.001), requirements for blood and blood products (30.8% versus 45.3%; P <.001), the frequency of reopening for bleeding (0.6% versus 2.8%; P <.001), requirements for postoperative intra-aortic balloon pump (1.3% versus 2.6%; P <.001), the frequency of atrial fibrillation OPCAB group. The mortality rate was 0.97% and 1.86% in the OPCAB and the CCAB groups, respectively (P <.001). Intensive care unit stays (23 +/- 6 hours versus 34 +/- 8 hours; P <.001) and hospital stays (5 +/- 2 days versus 8 +/- 3 days; P <.001) were significantly shorter in the OPCAB group. CONCLUSION: OPCAB is a safe and effective procedure for patients with multivessel coronary artery disease and is associated with reduced morbidity and mortality. However, large randomized studies with long-term follow-up may show the real benefits of OPCAB compared with CABG on CPB.

Aged↗

PubMed2002

Safety and efficacy of one stage off-pump coronary artery operation and carotid endarterectomy.

BACKGROUND: Patients with concomitant occlusive disease of coronary and carotid arteries remain at high risk of perioperative stroke and myocardial infarction. Combined coronary artery bypass grafting on cardiopulmonary bypass and carotid endarterectomy has been shown to give good results for this category of patients. In the present study, we analyzed our results of off-pump coronary artery bypass grafting and carotid endarterectomy as a one-stage procedure. METHODS: Between January 1997 and December 2000, 82 patients underwent combined off-pump coronary artery bypass grafting and carotid endarterectomy. All patients were evaluated by preoperative carotid duplex scanning and carotid angiography. All patients had more than or equal to 70% carotid artery stenosis. There were 35 asymptomatic patients (42.7%) and 47 symptomatic patients (57.3%). Carotid endarterectomy was performed before coronary artery bypass grafting in all the patients. RESULTS: There were 66 males (80.5%) and 16 females (19.5%) with a mean age of 63+/-8 years. The average number of grafts was 3.4+/-0.8. There was no hospital mortality. One patient had perioperative myocardial infarction. None of the patients had stroke. One patient had transient neurologic deficit and 1 patient had temporary 12th nerve dysfunction; both recovered completely. There was no incidence of neck wound infection, although 1 patient developed neck hematoma that required reexploration. At a mean follow-up of 2.2+/-0.7 years, 1 patient required contralateral carotid endarterectomy and 1 patient died because of cardiac failure. CONCLUSIONS: Combined off-pump coronary artery bypass grafting and carotid endarterectomy is a safe and effective procedure in patients with significant concomitant carotid and coronary artery disease.

Aged↗

PubMed2002

Off-pump multivessel coronary artery surgery in high-risk patients.

BACKGROUND: Coronary artery bypass surgery on cardiopulmonary bypass is associated with significant morbidity and mortality, which may be more marked in high-risk patients. We evaluated our results of off-pump coronary artery bypass (OPCAB) in high-risk patients with multivessel coronary artery disease and compared them with results in similar patients who underwent operation on cardiopulmonary bypass. METHODS: A total of 1,075 patients who underwent OPCAB between October 1996 and June 2001 and who had one or more of the following risk factors were included in the study: poor left ventricular function (EF < or = 30%), advanced age (> 70 years), left main stenosis, acute myocardial infarction, and redo coronary artery surgery. These patients were compared with 2,312 similar patients who underwent coronary artery bypass grafting on cardiopulmonary bypass during the same period. Preoperative risk factors, intraoperative variables, and postoperative results were analyzed and compared between two groups. RESULTS: The average number of grafts was 3.0 +/- 0.4 and 3.2 +/- 0.3 in the off-pump (OPCAB) and on-pump (CCAB) groups, respectively. Hospital mortality was 3.2% and 4.5% in OPCAB and CCAB groups respectively (p = 0.109). Perioperative myocardial infarction, requirement of inotropic agents, stroke, and renal dysfunction were comparable in two groups. Intubation time (19 +/- 5 vs 24 +/- 6 hours, p < 0.001), mean blood loss (362 +/- 53 vs 580 +/- 66 mL, p < 0.001), atrial fibrillation (14.3 vs 19.7%, p < 0.001), and prolonged ventilation (4.6 vs 7.6%, p = 0.002) were less in OPCAB group. Intensive care unit stay (20 +/- 8 hours) and hospital stay (6 +/- 3 days) were significantly less in the OPCAB group (p < 0.001). CONCLUSIONS: Off-pump coronary artery surgery can be safely performed in high-risk patients with multivessel coronary artery disease. Operative mortality is comparable to that associated with on-pump surgery, and avoidance of cardiopulmonary bypass is associated with reduced postoperative morbidity in these patients.

Age Factors↗

PubMed2002

Vascular complications of intra-aortic balloon insertion in patients undergoing coronary reavscularization: analysis of 911 cases.

OBJECTIVE: Intra-aortic balloon pump (IABP) is a well-accepted and widely used mechanical circulatory support in cardiac surgical practice. We evaluated the vascular complications of IABP and risk factors associated with the development of these complications in patients undergoing myocardial revascularization. METHODS: Between January 1994 and December 2000, a total of 911 patients undergoing coronary artery bypass grafting received IABP. The preoperative risk factors, balloon-related variables and vascular complications were studied and analyzed. Univariate and multivariate analyses were performed to identify risk factors for the development of vascular complications. RESULTS: Mean age of the patients was 59.2+/-9.1 years and 10.5% of the patients were female. The incidence of diabetes and peripheral vascular disease was 41.1 and 8.5%, respectively. The mean Parsonnet score was 11.8+/-4.6. IABP was inserted by percutaneous technique in 96.8% of patients. The duration of IABP therapy ranged from 20 h to 21 days (mean 3.8 days). Fifty-four (5.9%) patients developed major and 53 (5.8%) patients developed minor vascular complications. Ischaemia of the limb, requiring thromboembolectomy, developed in 25 (2.7%) patients. Patients who received IABP preoperatively had higher incidence of major vascular complications as compared to patients who received IABP in operating room before induction of anaesthesia. Multiple logistic regression analysis revealed age, triple vessel disease, indications of IABP therapy (unstable angina, cardiac arrhythmia and haemodynamic instability), left ventricular aneurysm surgery and use of balloon with sheath as independent risk factors for the development of vascular complications. CONCLUSIONS: IABP therapy is associated with certain vascular complications, which should always be kept in mind before insertion of a balloon. The use of a balloon without sheath and proper evaluation of peripheral circulation can help to minimize the development of vascular complications.

Aged↗

PubMed2002

Hemodynamic changes during displacement of the beating heart using epicardial stabilization for off-pump coronary artery bypass graft surgery.

OBJECTIVE: To evaluate the hemodynamic alterations during off-pump coronary artery bypass graft surgery to determine the degree of impairment caused and the techniques to rectify them. DESIGN: Prospective, observational cohort study performed from January 2000 through September 2000. PARTICIPANTS: Patients (n = 500) with coronary artery disease undergoing multivessel off-pump coronary artery bypass graft surgery using the Octopus tissue stabilizer (Medtronic, Inc, Minneapolis, MN). Unstable patients with ongoing ischemia were excluded from the study. INTERVENTIONS: All patients were monitored with radial artery and pulmonary artery catheters and continuous transesophageal echocardiography monitoring with a multiplane transducer. The perioperative requirement of an intracoronary shunt, inotropes, or an intra-aortic balloon pump was noted. The effect of the Trendelenburg position and fluids on hemodynamics was observed. The need for defibrillation and institution of emergency cardiopulmonary bypass were major endpoints to determine the inability of the patient to tolerate displacement of the heart. MEASUREMENTS AND MAIN RESULTS: Mean patient age was 59.3 +/- 11.6 years. There were 204 (40%) patients in the high-risk category; 54 (10.8%) patients had left ventricular ejection fraction <25%. The mean number of grafts was 2.7 +/- 0.8. Vertical displacement of the heart to access the lateral and inferior walls decreased the mean arterial pressure by 18 +/- 4% (p < 0.01), with a concomitant increase in central venous pressure of 66 +/- 18% (p < 0.001). The stroke volume and the cardiac index were reduced by 35.7 +/- 11% (p < 0.001) and 45 +/- 13% (p < 0.001). On transesophageal echocardiography, there was development of new regional wall motion abnormalities in 59.2% and a decrease in global left ventricular functions in 61.2%. The use of inotropes was highest during anastomosis on the posterior wall-78.4% compared with 21.9% for the anterior wall. An intra-aortic balloon pump was used in 55 (11.2%) patients, and 7 (0.71 %) patients had to be put on emergency CPB. The in-hospital mortality was 1.2%. CONCLUSION: Most patients had hemodynamic changes easily correctable by fluids and inotropes. Monitoring of left ventricular and right ventricular function by transesophageal echocardiography enhances safety of the procedure and is recommended. The use of the Octopus II tissue stabilizer proved to be a safe and versatile means to stabilize the heart during off-pump coronary artery bypass procedures, especially in high-risk patients.

Cardiopulmonary Bypass↗

PubMed2002

Comparison of continuous, stat, and intermittent cardiac output measurements in patients undergoing minimally invasive direct coronary artery bypass surgery.

OBJECTIVE: To compare intermittent cardiac output (ICO) with continuous cardiac output (CCO) and stat cardiac output (SCO) measurements in patients undergoing minimally invasive direct coronary artery bypass (MIDCAB) surgery. DESIGN: Prospective, clinical study. SETTING: Single, tertiary referral center. PARTICIPANTS: Twenty adult patients undergoing off-pump MIDCAB surgery from January through June 2000. INTERVENTIONS: Each patient had a 7.5F 5-lumen pulmonary artery thermodilution catheter (CCO catheter, Baxter Healthcare Corporation, Irvine, CA) inserted for measurement of cardiac output (CO). ICO, CCO, and SCO were compared at 10 predefined time points. RESULTS: A total of 400 data pairs for CO were obtained. ICO values ranged from 1.8 to 8.4 L/min; CCO, 1.9 to 7.5 L/min; and SCO, 2.25 to 6.35 L/min. Correlation between ICO and CCO was significant (correlation coefficient, r = 0.78, p < 0.001), accompanied by a bias of -0.095 L/min and precision of 0.729 L/min. Similarly, the correlation between ICO and SCO was significant (r = 0.79, p < 0.001), accompanied by good accuracy (bias, 0.084 L/min) and precision (0.843 L/min). There were statistically significant decreases in mean arterial pressure, CO, cardiac index, stroke volume, stroke volume index, and left and right ventricular stroke work indices during anastomosis of the left internal mammary artery to left anterior descending artery. These parameters returned to baseline preinduction values 1 minute after completion of the anastomosis. CONCLUSION: Excellent correlation, accuracy, and precision were found among the 3 methods of measuring CO in patients undergoing MIDCAB surgery. Further studies are needed to assess their accuracy in multivessel off-pump coronary artery bypass graft surgery and in patients with poor left ventricular function.

Cardiac Output↗

PubMed2002

Routine use of the radial artery for coronary artery revascularization.

Between January 1997 and December 2000, a total of 4,000 patients underwent myocardial revascularization using the radial artery as one of the conduits. The mean age of the patients was 54 +/- 7 years, and 92.8% of them were male. Of these patients, 31% had a left ventricular ejection fraction below 40% and 22.8% underwent urgent operation. A total of 4,225 distal anastomoses were performed using the radial artery. The average number of grafts was 3.3 +/- 0.5. The hospital mortality rate was 0.8%. Low cardiac output, inotropic support, perioperative myocardial infarction, reoperation for bleeding, atrial fibrillation, and sternal infection occurred in 1.8%, 2.8%, 1.2%, 1.2%, 16.8%, and 1.2% of the patients, respectively. None of the patients had major ischemia of the hand. The incidence of local hand wound complications was 0.7% (wound infection, 0.4%; wound dehiscence without infection, 0.1%; and hematoma, 0.2%). The average length of stay in the intensive care unit was 20 +/- 7 hours and in the hospital was 6 +/- 2 days. Postoperative angiography, performed in 106 patients at a mean interval of 18 months, showed that 92.4% of radial artery, 96.2% of internal mammary artery, and 76.2% of saphenous vein grafts were patent.

Anastomosis, Surgical↗

PubMed2002

Robotically controlled video-assisted port-access mitral valve surgery.

From 1997 to 2000, 221 patients underwent mitral valve surgery through a mini-thoracotomy, using a port-access endovascular cardiopulmonary bypass system in 38 and a transthoracic clamp in 183. In 120 patients, exposure of the mitral valve was facilitated by an endoscope attached to a voice-controlled robotic arm (AESOP 3000). The mitral valve was repaired in 26 patients and replaced in 195; 24 were redo cases. Operating time was 3.5 +/- 1.2 hours, aortic crossclamp time was 58 +/- 16 minutes, intensive care unit stay was 22 +/- 7 hours, and hospital stay was 6.4 +/- 1.2 days. Median postoperative blood loss was 332 +/- 104 mL. There was 1 hospital death. On follow-up at 16.4 +/- 12.2 months, there was no late death or reoperation. New York Heart Association functional class improved from 2.6 +/- 0.5 to 1.4 +/- 0.8. Use of video and robotic assistance minimized incision length and allowed visualization of the whole mitral valve apparatus. The transthoracic clamp facilitated aortic crossclamping and injection of cardioplegia. These findings indicate that the procedure is safe and effective and suggest advantages over conventional surgery in terms of cost, cosmesis, blood loss, postoperative discomfort, intensive care unit and hospital stay.

Adult↗

PubMed2002

Off-pump coronary artery surgery in the elderly.

We compared the results of off-pump (n = 186) and on-pump (n = 389) coronary artery bypass grafting in elderly patients over 70 years old. Patients undergoing single-vessel revascularization were excluded from the study. The 2 groups matched in preoperative risk factors. Operative mortality was comparable (off-pump 2.2% versus on-pump 4.6%). The off-pump group fared better in intubation time (16 +/- 4 hours versus 25 +/- 5 hours), blood loss (365 +/- 58 mL versus 584 +/- 72 mL), the need for blood transfusion (31.7% versus 44%), reoperation for bleeding (0.5% versus 3.6%), atrial fibrillation (10.2% versus 18.5%), intensive care unit stay (21 +/- 8 hours versus 34 +/- 10 hours), and total hospital stay (5 +/- 2 days versus 8 +/- 3 days). Off-pump bypass surgery is thus safe for elderly patients and is associated with reduced morbidity and shorter hospitalization than on-pump surgery.

Age Factors↗

PubMed2002

Redo mitral valve surgery using the port-access system.

Redo mitral valve surgery is hazardous, hence we explored an alternative approach using a port-access system that avoids reentry. Between October 1997 and December 2000, 32 patients underwent mitral reoperation using the system. All patients had previous cardiac operations. This procedure consisted of a right anterolateral minithoracotomy and femorofemoral cannulation using special port-access instruments and endoaortic clamping in 24 patients or direct transthoracic sliding-rod aortic clamping in 8. The valve disease was of rheumatic etiology in 28 patients and degenerative in 4. The valve was replaced in 31 cases and a paravalvular leak after mitral valve replacement was closed in 1. In 2 cases, the tricuspid valve was repaired along with mitral valve replacement. Mean total operating time was 4.5 +/- 1.2 hours, cardiopulmonary bypass time 162 +/- 72 minutes, and aortic crossclamp time 62 +/- 21 minutes. There was no mortality, and mean stay in the intensive care unit was 22 +/- 7 hours and hospital stay 6.4 +/- 1.2 days. Postoperative blood transfusion was required in 12 patients. In view of the favorable results, we recommend using the port-access system as a standard approach for mitral reoperation.

Adult↗

PubMed2002

Neuroleptic malignant syndrome: uncommon postoperative diagnostic dilemma.

Neuroleptic malignant syndrome occurred in a 71-year-old man on haloperidol therapy for mild depressive dementia. After coronary artery bypass grafting, he developed hyperthermia, elevated creatine kinase without a corresponding rise in the MB-isoenzyme, leukocytosis, raised liver enzymes, urea, and creatinine. His condition responded to bromocriptine therapy.

Aged↗

PubMed2002

Off-pump coronary artery bypass grafting in patients with left ventricular dysfunction.

BACKGROUND: Coronary artery bypass grafting in patients with severe left ventricular (LV) dysfunction still remains a high risk procedure due to its high mortality and morbidity. Off-pump surgery can be an alternative technique in these patients. We analyzed our results of off-pump coronary surgery in patients with left ventricular dysfunction and compared them with patients operated on-pump. METHODS: Between January 1997 and December 2000, 355 patients with LV dysfunction (EF equal to or less than 30%) underwent off-pump coronary artery bypass (OPCAB) surgery. During the same period, 959 patients with LV dysfunction underwent coronary artery surgery on cardiopulmonary bypass. Octopus was used as mechanical stabilizer and intracoronary shunts were used in most patients. The mean age of the patients was 57.7 +/- 9.2 in patients operated on-pump and 58.4 +/- 9.8 in patients operated off-pump. RESULTS: The preoperative variables were comparable in two groups, except that there were more patients with triple vessel disease in on-pump group. Average number of grafts was 2.8 +/- 0.7 and 3.3 +/- 0.7 (p<0.001) in off-pump and on-pump groups respectively. The mortality was 3.9% and 6.0% (p = 0.176) in off-pump and on-pump groups respectively. Postoperative morbidity was less in off-pump group but it was statistically significant in incidence of atrial fibrillation and prolonged ventilation which were low in off-pump group. The hospital stay was significantly less in patients operated off-pump. CONCLUSION: OPCAB surgery can be safely performed in patients with LV dysfunction. The postoperative morbidity and length of stay is less as compared to patients operated on-pump.

Cardiopulmonary Bypass↗

PubMed1999

Echocardiography in Minimally Invasive Direct Coronary Artery Bypass.

Minimally invasive direct coronary artery bypass (MIDCAB) is a recently developed, less-invasive alternative to standard bypass surgery. MIDCAB is performed through a small incision (2-3 inches) on the beating heart without the use of cardiopulmonary bypass or cardioplegia. It is associated with less trauma and a shorter hospital stay than conventional surgery. Transesophageal echocardiography helps in patient selection by detecting protruding aortic atheromas (PATHs), which are associated with a high risk of stroke during typical cardiopulmonary bypass. MIDCAB may be the technique of choice in patients with PATHs. Intraoperative echocardiography can detect wall motion abnormalities and helps in determining intraoperative myocardial ischemia and the postoperative prognosis. Duplex study of the internal mammary arteries is helpful in evaluating coronary anastomosis patency. Characteristically, a patent coronary anastomosis demonstrates a high diastolic flow fraction, with a ratio between peak diastolic and peak systolic flow velocity of > 1.

Journal Article↗