Removal of infected pacemaker leads with deep hypothermic circulatory arrest and open surgical exploration of the superior vena cava and innominate veins.

Despite the use of transvenous methods for extraction of infected leads, failed attempts may result in retained lead fragments. Retained lead fragments may be a focus of continued infection leading to sepsis. We present two patients in which conversion from cardiopulmonary bypass to hypothermic circulatory arrest allowed direct visualization, using venotomies in the superior vena cava and innominate vein to achieve complete removal of retained pacemaker lead fragments. Use of venotomies in the extracardiac venous system is a technical addition to prior descriptions of lead extraction using deep hypothermia and circulatory arrest.

Routine myocardial revascularization with the radial artery: a multicenter experience.

BACKGROUND: Current literature documents use of the radial artery (RA) for myocardial revascularization only as an alternative conduit in cases where the saphenous veins have been previously harvested or are unsuitable for use. Large-scale routine clinical use of the RA as the conduit of choice has not been reported. METHODS: This prospective study evaluated the harvest of the RA from 933 patients and the subsequent use of the conduit as a preferred coronary artery bypass graft second only to the left internal thoracic artery in 930 of these patients. RESULTS: Unilateral RA harvest was performed in 786 patients and 147 patients had bilateral RA harvest. A total of 1080 RAs were harvested; 214 (19.8%) originated from the dominant forearm. There was a mean of 3.30+/-0.93 grafts per patient of which 2.43+/-0.83 were arterial grafts. The mean number of RA grafts was 1.43+/-0.53. Operative mortality was 2.3% with none due to the RA graft(s). There was no ischemia nor motor dysfunction in the operated hands. Thirty-two (3.4%) patients experienced transient thenar dysesthesia that resolved in 1 day to 6 weeks. CONCLUSIONS: Our results demonstrate that routine total or near total arterial myocardial revascularization may be achieved safely and effectively with the use of one or both RAs in conjunction with the internal thoracic artery.

Pathology of the radial and internal thoracic arteries used as coronary artery bypass grafts.

BACKGROUND: This investigation compared the incidence and the degree of atherosclerosis present in radial artery (RA) and internal thoracic artery segments remaining after coronary artery bypass grafting. METHODS: One hundred seventy specimens from 102 patients were histologically analyzed, including 106 RA specimens. RESULTS: The mean degree of pathology for the RA was 0.89 on a 0 (none) to 4 (lumen completely obliterated) scale; the mean grade of pathology for the internal thoracic artery was 0.30 (p < 0.001). Presence of diabetes, aortofemoral disease, femoral-popliteal disease, age, and male gender correlated with an increase in RA pathology. Flow in the in situ RA did not correlate with the degree of pathology. CONCLUSIONS: Study of the excess RA and internal thoracic artery segments remaining after coronary artery bypass grafting demonstrated that the RA had a higher degree of atherosclerosis than the internal thoracic artery at the time of harvest. Overall severity of disease in the RA was low. The long-term performance of RA grafts will determine whether this level of atherosclerotic disease has any clinical significance.

Evaluation of acute ischemic mitral regurgitation following cardiopulmonary bypass assessed by biplane transesophageal echocardiography.

The aim of this study was to evaluate pathogenesis and outcome of acute ischemic mitral regurgitation (MR) in patients undergoing coronary artery bypass grafting (CABG) using biplane transesophageal echocardiography (TEE). Biplane TEE was continuously monitored in a total of 96 patients who were scheduled for elective CABG surgery. Of 96 patients, 10 with no MR at stages 1 (after anesthetic induction but before skin incision) and 2 (after cardiopulmonary bypass [CPB] and decannulation) were excluded. In the remaining 86 patients with MR between stages 1 and 2, 45 (group A) had an increase in MR, and 41 (group B) had a decrease in MR. An increase in MR at stage 2 in group A was associated with a significant increase in annular diameter (p < 0.05), and pulmonary capillary wedge pressure (p < 0.01) compared with stage 1. A significant decrease in the left ventricular end-diastolic area (p < 0.01), end-systolic area (p < 0.05) and the mean wall motion abnormality score (WMA score) (p < 0.001) was observed at stage 2 compared with stage 1 in group B. In 16 of 17 patients (94%) with an increased WMA score in group A, a regional wall motion abnormality (RWMA) was detected in the right coronary artery (RCA) and/or left circumflex coronary artery (LCX) areas. In 7 patients in group A, MR increased continuously until stage 3 (after sternal closure) despite treatment. In 2 of these 7 patients, pulmonary venous systolic flow (PVSF) decreased during stage 2 and persisted to stage 3. The post operative course of these 2 patients was complicated with atrial fibrillation (AF). The increase in annular diameter and worsening in RWMA in RCA and/or LCX areas are associated with acute ischemic MR following CPB. The majority of acute ischemic MR cases were resolved by pharmacological intervention. Post operative AF was noted in 2 patients with acute ischemic MR associated with persistently decreased PVSF following CPB despite treatment.

Use of a free radial artery graft for correction of Bland-White-Garland syndrome.

A radial artery free graft was used to create a two-coronary artery system for a 15-month-old child with Bland-White-Garland syndrome. The anomalous left main coronary artery originated from the proximal right pulmonary artery.

Routine use of unilateral and bilateral radial arteries for coronary artery bypass graft surgery.

OBJECTIVES: This study sought to evaluate the routine use of radial artery (RA) grafts in patients undergoing coronary artery revascularization. BACKGROUND: Previous long-term studies have documented poor patency of saphenous vein grafts compared with internal thoracic artery (ITA) grafts. METHODS: We performed a prospective review of 175 of 249 consecutive patients. RESULTS: Fifty-four patients had bilateral RAs harvested. Mean number (+/- SD) of grafts/patient was 3.27 +/- 0.93, with 2.76 +/- 0.97 arterial grafts; a mean of 1.53 +/- 0.68 grafts were performed with the RA. The operative mortality rate was 1.6%. No deaths were related to RA grafts, and there were no RA harvest site hematomas or infections. Transient dysesthesia 1 day to 4 weeks in duration occurred in the distribution of the lateral antebrachial cutaneous nerve in six extremities (2.6%). Elective cardiac catheterization in 60 patients at 12 weeks postoperatively demonstrated a 95.7% patency rate. CONCLUSIONS: Because of potential benefit of long-term patency associated with arterial grafts, minimal morbidity and mortality associated with use of the RA and excellent short-term patency rates, we cautiously recommend use of one or both RAs as additional conduits to be used concomitantly with the ITA for arterial revascularization of the coronary arteries.

Early postoperative angiographic assessment of radial grafts used for coronary artery bypass grafting.

UNLABELLED: Despite a revival of interest in using the radial artery as an alternative conduit for myocardial revascularization, little angiographic documentation of early postoperative results has been presented, particularly in North America. Accordingly, 60 of 150 patients who underwent coronary artery bypass with radial arteries from November 1993 to July 1995 have had postoperative cardiac catheterization at our institution. The patency rate of the radial artery grafts was 95.7% (90 of 94 grafts patent) with an average internal diameter of 2.51 mm. Four radial artery grafts showed diffuse narrowing. The patency rate of the internal thoracic artery grafts was 100% with an average internal diameter of 2.25 mm. Three of 62 grafts demonstrated diffuse narrowing. Two of 24 (7.7%) saphenous vein grafts were occluded; the average internal diameter was 3.23 mm. The internal thoracic artery, the radial artery, and saphenous vein grafts were, respectively, 7.5%, 19.5%, and 53.3% larger than the anastomosed native coronary arteries. Graft-dependent flow was found in 81.1% of the radial artery grafts. CONCLUSION: The results of this study demonstrate that the short-term patency rate of radial artery grafts is excellent.

Atrial natriuretic peptide replacement therapy in rats subjected to biatrial appendectomy.

The postoperative fluid retention found in some patients after the Cox maze procedure has been attributed to surgically induced loss of atrial natriuretic peptide. We postulated that exogenous atrial natriuretic peptide could reverse this antidiuresis. A rat model was used to investigate this hypothesis. In group I, the sham group, the atrial appendages were left intact and the animals were then subjected to a fluid challenge equivalent to 1% of the animal's body weight. In group II, after biatrial appendectomy, the animals were subjected to a fluid challenge similar to that in group I. Animals in group III underwent the same protocol as that for group II plus intravenous administration of atriopeptin III at varying concentrations. Urine output and plasma atrial natriuretic peptide levels were significantly decreased after biatrial appendectomies (p < or = 0.01). Urine output returned to control levels after biatrial appendectomies with low-dose atrial natriuretic peptide infusion (0.5 pmol/min = 25.5 pg/min), although circulating atrial natriuretic peptide levels were lower. Urine output and plasma atrial natriuretic peptide levels increased with atrial natriuretic peptide infusions between 0.5 and 50 pmol/min. Heart rate and mean blood pressure did not vary significantly with atrial natriuretic peptide infusions. Thus atrial natriuretic peptide can be used effectively in low doses to induce a diuresis after biatrial appendectomies. Atrial natriuretic peptide may have clinical application after the Cox maze procedure.

Technique for harvesting the radial artery as a coronary artery bypass graft.

The radial artery was proposed and then abandoned as a coronary artery bypass graft in the 1970s. Development of new pharmacologic antispasmodic agents and minimally traumatic harvesting techniques has led to a revival of the use of the radial artery in coronary artery bypass procedures. Unlike the saphenous vein in the lower extremities, the radial artery in the volar forearm is not a subcutaneous structure. Safe harvest of the artery requires an understanding of volar forearm anatomy. Based on review of anatomy, cadaver dissection, and clinical experience with 40 patients, we have developed a technique for radial artery harvest. The volar forearm is divided into three zones: the proximal zone, the middle zone, and the distal zone. In each zone, important anatomic landmarks are identified. Our harvesting technique has resulted in minimal postoperative morbidity and no postoperative ischemic complications. Although the pedicled internal thoracic artery graft remains the primary arterial conduit for myocardial revascularization, the radial artery is an excellent additional bypass conduit.

Wound healing after harvesting of the internal thoracic and the superior and inferior epigastric arteries.

Wound healing of sternal incisions and midline or paramedian abdominal incisions was studied at 2 weeks postoperatively in three groups of dogs. Group 1, 10 dogs, had harvesting of bilateral internal thoracic arteries, superior epigastric arteries, and inferior epigastric arteries. Group 2, 5 dogs, had removal of the same arteries, but the superior and inferior epigastric arteries were harvested through paramedian rather than midline incisions. Group 3, 5 dogs, served as control and had median sternotomies and midline abdominal incisions only. All wounds healed without complication. Wound breaking strength of the skin of the chest incisions was significantly greater (p < 0.05) in the control group (group 3) (52.6 lb) compared with groups 1 (38.0 lb) and 2 (34.8 lb). Wound breaking strength of the skin of the abdominal incisions was significantly greater (p < 0.05) in group 2 (50.4 lb) when paramedian incisions were made compared with group 1 (35.1 lb). Hydroxyproline content was similar for all groups and all incisions. We conclude that abdominal wound breaking strength is significantly greater when paramedian incisions are performed to harvest the inferior epigastric arteries. Harvesting bilateral internal thoracic, superior epigastric, and inferior epigastric arteries may lower sternal wound breaking strength.

Ultrasound evaluation of the inferior epigastric artery.

Color-flow Doppler ultrasound was used to assess the anatomic characteristics of the inferior epigastric artery (IEA) bilaterally in 20 nonatherosclerotic (group I; mean age, 28 years) and 20 atherosclerotic (group II; mean age, 57 years) subjects. Forty-nine percent of the IEAs were located laterally within the rectus sheath with 34% in a mid and 17% in a medial location. Seventeen percent had a large branch within 5 cm of the origin. Average length of the IEA was 10.7 +/- 3.2 cm. Average proximal and distal internal diameters were 3.0 +/- 0.45 and 1.9 +/- 0.35 mm, respectively. Neither length nor vessel diameter showed any correlation with age or body surface area. Sixty-two percent of the IEAs were greater than or equal to 9 cm in length and 1.5 mm in distal diameter. Stenosis of the vessel (more than 50% diameter) was noted at the proximal 1 cm segment in 20% of the IEAs in the atherosclerotic group but none of the IEAs in the nonatherosclerotic group. Beyond this proximal segment, there was freedom from atherosclerotic stenosis as demonstrated by the IEAs' similarity of length and diameter irrespective of age in these atherosclerotic and nonatherosclerotic populations.

Use of neurosurgical techniques for removal of a cardiac tumor.

A 6-week-old male infant with a capillary hemangioma of the right atrioventricular groove adjacent to the right coronary artery and conduction system underwent successful resection with the aid of microneurosurgical instrumentation. The technical challenge was thought to be analogous to that encountered by microneurosurgeons in their dissection of brain tumors.

ICD implantation via thoracoscopy, "mailslot" thoracotomy, and subxiphoid incision.

An improved method of thoracoscopic implantable cardioverter defibrillators implantation is described. "Mailslot" thoracotomy is more expeditious than thoracoscopic implantation via multiple ports. If required for adequate defibrillation thresholds, subxiphoid, subdiaphragmatic implantation of a defibrillator patch may be performed.

Surgical removal of infected transvenous pacemaker leads.

Infection, though uncommon, can be the most lethal of all potential complications following transvenous pacemaker implantation. Eradication of infection associated with pacemakers requires complete removal of all hardware, including inactive leads. Since 1972, 5,089 patients have had 8,508 pacemaker generators implanted at Montefiore Medical Center. There were 91 infections (1.06%); four of our patients required surgical removal. Nine additional patients were referred for surgical removal of infected transvenous pacemaker leads from other institutions. Surgical methods for removal included use of cardiopulmonary bypass or inflow occlusion. Surgery may be safely used in unstable or elderly patients and should not be reserved as a last resort. This article reviews our surgical experience removing infected pacemaker leads at Montefiore Medical Center.

Comparison of left ventricular cryolesions created by liquid nitrogen and nitrous oxide.

OBJECTIVES: This study was designed to compare the cryosurgical lesions produced by liquid nitrogen (-196 degrees C) and nitrous oxide (-76 degrees C). BACKGROUND: Cryosurgical ablation is a useful method of arrhythmia surgery, but information on the dimensions of cardiac lesions produced by modifying cryoprobe temperature is limited. METHODS: We compared the dimensions, volumes and electrophysiologic effects of cryolesions created by a liquid nitrogen cryoprobe (Group I) and a nitrous oxide cryoprobe (Group II) on the left ventricular myocardium in the beating canine heart. Exposure time was compared at 1, 2, 3 and 4 min. In each of 18 dogs, two to four lesions were created on the left ventricle and analyzed: 35 lesions created with use of the nitrous oxide cryoprobe and 30 lesions created with the liquid nitrogen cryoprobe. Lesions were measured at the time of induced death 6 weeks postoperatively and assessed by tissue staining with the Masson trichrome technique. RESULTS: The volumes (mm3) of the cryolesions created by the liquid nitrogen cryoprobe were significantly larger (p < 0.05) than those of lesions created by nitrous oxide: 826 +/- 163 versus 493 +/- 197 at 1 min; 1,101 +/- 327 versus 666 +/- 185 at 2 min; 1,356 +/- 318 versus 787 +/- 258 at 3 min and 1,735 +/- 534 versus 923 +/- 376 at 4 min. CONCLUSIONS: Decreasing the temperature of the cryoprobe by using liquid nitrogen increases the volume of the lesions. Programmed electrical stimulation before and 6 weeks after cryoablation indicated no arrhythmogenicity.

Combined maze procedure and septal myectomy in a septuagenarian.

A 75-year-old woman with refractory paroxysmal atrial fibrillation and hypertrophic obstructive cardiomyopathy underwent a successful combined maze procedure and septal myectomy. Postoperative episodes of atrial fibrillation and flutter occurred only during periods of bradyarrhythmia and did not recur with atrial inhibited pacing.

Histological evaluation of the inferior epigastric artery in patients with known atherosclerosis.

Comparative histological studies have been performed on the various arterial conduits available for myocardial revascularization including the inferior epigastric artery which has recently become the focus of intense investigation. In this study, 10 patients with known risk factors for atherosclerotic disease had their inferior epigastric artery harvested and the entire specimen examined for the microscopical presence of atherosclerosis or its precursors. Histopathological findings that have been shown to be theoretically protective against the progression of atherosclerosis were observed. These include the paucity of fenestrae in the internal elastic lamina, no medical calcification, the absence of foam cells and the absence of intimal smooth muscle cells. No specimen had atherosclerotic disease and only 3 specimens showed changes consistent with minimal intimal hyperplasia. Morphometric analysis of the 3 diseased specimens revealed only minimal luminal narrowing. These findings suggest that the inferior epigastric artery may not be prone to atherosclerosis. Thus, the inferior epigastric artery appears to be a safe myocardial conduit and long-term patency can be anticipated.