Cannula Placement for Cerebral Protection Without Circulatory Arrest in Patients Undergoing Hemiarch Aortic Aneurysm Repair

BACKGROUND

Aortic aneurysms involving the proximal aortic arch, which require hemiarch-type repair, typically require circulatory arrest with antegrade cerebral perfusion. Left carotid antegrade cerebral perfusion (LCP) via distal arch cannulation without circulatory arrest was used in this study's patient population. The goal was to assess the operative efficiency and clinical outcomes of using a distal arch cannulation technique that would not require any hypothermic circulatory arrest (HCA) time compared with more traditional brachiocephalic artery cannulation with right-sided unilateral antegrade cerebral perfusion (RCP) and HCA.

METHODS

A single-center retrospective review of patients with replacement of the distal ascending aorta involving the proximal arch was performed. Patients with an intramural hematoma or dissection were excluded. Between January 2015 and December 2019, 68 adult patients had undergone a hemiarch repair because of aneurysmal disease. Analysis of baseline demographics, operative data, and clinical outcomes was performed.

RESULTS

Comparing the 68 patients: 21 patients were treated with RCP (via brachiocephalic artery graft with HCA), and 47 patients were treated with LCP (via distal aortic arch cannulation with cross-clamp between the brachiocephalic and left common carotid arteries without HCA). Baseline characteristics and outcomes were evaluated for both groups. The LCP group was younger (LCP median [IQR] age, 60 [53-65] years vs RCP median [IQR] age, 67 [59-71] years]. Sex, race, body mass index, comorbidities, and ejection fraction were similar between the groups. Cardiopulmonary bypass time (LCP, 123 minutes vs RCP, 149 minutes) and unilateral cerebral perfusion time (LCP, 17 minutes vs RCP, 22 minutes) were longer in the RCP group. Bleeding, prolonged ventilatory support, kidney failure, and length of stay were similar. In-hospital mortality was 2% in the LCP group vs 0% in the RCP group. Stroke occurred in 2 patients (4.2%) in the LCP group and in 0% of the RCP group. Mortality at 6 months in the LCP and RCP groups was 3% and 10%, respectively.

CONCLUSION

Distal arch cannulation with LCP without HCA is a reasonable and safe alternative strategy for patients requiring hemiarch replacement for aneurysmal disease. This technique may provide additional benefits by avoiding circulatory arrest in these complex cases.

Dual Left Main Coronary Arteries With Ischemia and Coronary Steal

A 59-year-old man had angina and an abnormal perfusion scan. Work-up revealed 2 left main coronary arteries: the anomalous artery originated from the right coronary cusp and took an aberrant interventricular septal course; the other artery was atretic. He underwent surgical unroofing, with resolution of symptoms. (Level of Difficulty: Intermediate.)

Aortic root replacement with Medtronic Freestyle bioprosthesis: 25-year experience

BACKGROUND

Stentless porcine bioprothesis is a surgical strategy to treat aortic root disease. Use has been limited due to the concern for long-term valve degeneration. This study evaluated the perioperative and late outcomes of patients with aortic root disease requiring root replacement.

METHODS

A total of 409 patients underwent aortic root replacement by a single surgeon using a stentless porcine bioroot between February 1996 and May 2020. The cohort was divided into two groups (age ≤65 and >65 years). Descriptive statistics were used to analyze the data and Kaplan-Meier curves used to evaluate long-term outcomes.

RESULTS

Patients age >65 years were more likely to be female (p = .01), have hypertension (p = .01), require circulatory arrest (p = .01), and have concomitant coronary artery bypass grafting (CABG) (p = .04). Baseline creatinine >1.8 (p = .20), diabetes (p = .06), and ejection fraction (p = .20) were similar between groups. The 1-, 5-, and 10-year survival for patients age ≤65 years were 92%, 87%, and 69%, respectively, significantly better than patients age >65 (88%, 73%, and 43%, respectively) (p < .01, Figure 1). The 1-, 5-, and 10-year freedom from reoperation for patients ≤65 years were 99%, 97%, and 93% versus 99%, 98%, and 96% in patients age >65 years, respectively (p = .24).

CONCLUSION

Patients with aortic root disease can be treated with acceptable perioperative outcomes, long-term survival, and low reoperation rates using a stentless porcine bioprothesis. It should be considered irrespective of age due to its excellent durability and freedom from anti-coagulation requirement.

Is internal mammary artery graft beneficial in emergent coronary artery bypass surgery? A Society of Thoracic Surgeons national database analysis

BACKGROUND

Often, only saphenous vein grafts (SVGs) are used in emergent coronary artery bypass graft (CABG) procedures to provide quicker myocardial revascularization despite its lower long-term patency relative to the internal mammary artery (IMA) grafts. We examined differences between IMA and non-IMA graft recipients in emergent CABGs and its impact on in-hospital outcomes.

METHODS

Retrospective review of Society of Thoracic Surgeon National Database was done to identify patients age ≥18 years undergoing primary emergent isolated CABG between 2013 and 2016. Emergent salvage, non-LAD disease, subclavian stenosis and revascularization with other arterial grafts were excluded. The study population was divided in two groups: IMA and non-IMA groups. Demographics, preoperative, intraoperative factors and postoperative outcomes were analyzed between the groups.

RESULTS

Of 18,280 emergent CABGs during the study period, 16281 had IMA used and 1999 had only vein grafts. The IMA group was younger, more likely to be male, had lower creatinine and higher ejection fraction. The non-IMA and IMA groups were then propensity risk matched with ratio of 1:2 which showed significantly higher in-hospital mortality in the non-IMA group (15% vs. 7%, P<0.0001). The non-IMA groups also had higher rates bleeding (5% vs. 3%, P<0.01), renal failure (10% vs.6%, P<0.0001) and prolonged vent (44% vs. 30%, P<0.0001).

CONCLUSIONS

IMA grafts in primary isolated emergent CABGs are associated with significantly lower rates of in-hospital mortality. Even for emergent CABG there may be a clinical benefit in using IMA grafts rather than SVGs only.

Optimum surgical treatment for tricuspid valve infective endocarditis: An analysis of the Society of Thoracic Surgeons national database

OBJECTIVE

The incidence of intravenous drug-associated tricuspid valve endocarditis in the United States is rapidly increasing. Our goal was to evaluate the outcomes of isolated tricuspid valve operations using the Society of Thoracic Surgeon Adult Cardiac Surgical Database.

METHODS

From July 2011 to December 2016, 1613 patients with intravenous drug-associated tricuspid valve endocarditis underwent isolated tricuspid valve operations for endocarditis. Patients were stratified on the basis of type of tricuspid valve operation: valvectomy in 119 (7%), repair in 532 (33%), and replacement in 962 (60%). Risk factors and 30-day outcomes were compared among groups using Kruskal-Wallis and Pearson's chi-square tests. Multivariable logistic regression evaluated risk-adjusted operative mortality and morbidity by operative technique.

RESULTS

Age, gender, race, and renal function were comparable among groups. Compared with the repair and replacement groups, the valvectomy group had a higher rate of acute infection (90% vs 79%, 84%; P < .01), Model for End-Stage Liver Disease score (10.17 vs 8.44, 9.74, P < .01), and urgent/emergency surgery (91% vs 75%, 83%; P < .01), respectively. Operative mortality was higher in those undergoing valvectomy (16%) (P < .01) compared with repair (2%) or replacement (3%). After risk adjustment, valvectomy was associated with a higher risk of operative mortality compared with repair (odds ratio, 3.82; P < .01), whereas there was no difference in operative mortality between repair and replacement (odds ratio, 0.95; P = .89).

CONCLUSIONS

This contemporary series of intravenous drug-associated tricuspid valve endocarditis reveals that valvectomy is an independent predictor of operative mortality. When anatomically possible, repair should be the preferred management for tricuspid valve endocarditis to avoid recurrent valve infection and prosthetic valve degeneration.

Cerebral Oximetry for Cardiac and Vascular Surgery

The technology of transcranial near-infrared spectroscopy (NIRS) for the measurement of cerebral oxygen balance was introduced 25 years ago. Until very recently, there has been only occasional interest in its use during surgical monitoring. Now, however, substantial technologic advances and numerous clinical studies have, at least partly, succeeded in overcoming long-standing and widespread misunderstanding and skepticism regarding its value. Our goals are to clarify common misconceptions about near-infrared spectroscopy and acquaint the reader with the substantial literature that now supports cerebral oximetric monitoring in cardiac and major vascular surgery.

Effect of the stop-flow technique on cardiac retention of c-kit positive human cardiac stem cells after intracoronary infusion in a porcine model of chronic ischemic cardiomyopathy

It is commonly thought that the optimal method for intracoronary administration of cells is to stop coronary flow during cell infusion, in order to prolong cell/vascular wall contact, enhance adhesion, and promote extravasation of cells into the interstitial space. However, occlusion of a coronary artery with a balloon involves serious risks of vascular damage and/or dissection, particularly in non-stented segments such as those commonly found in patients with heart failure. It remains unknown whether the use of the stop-flow technique results in improved donor cell retention. Acute myocardial infarction was produced in 14 pigs. One to two months later, pigs received 10 million indium-111 oxyquinoline (oxine)-labeled c-kit(pos) human cardiac stem cells (hCSCs) via intracoronary infusion with (n = 7) or without (n = 7) balloon inflation. Pigs received cyclosporine to prevent acute graft rejection. Animals were euthanized 24 h later and hearts harvested for radioactivity measurements. With the stop-flow technique, the retention of hCSCs at 24 h was 5.41 ± 0.80 % of the injected dose (n = 7), compared with 4.87 ± 0.62 % without coronary occlusion (n = 7), (P = 0.60). When cells are delivered intracoronarily in a clinically relevant porcine model of chronic ischemic cardiomyopathy, the use of the stop-flow technique does not result in greater myocardial cell retention at 24 h compared with non-occlusive infusion. These results have practical implications for the design of cell therapy trials. Our observations suggest that the increased risk of complications secondary to coronary manipulation and occlusion is not warranted.

Safety of intracoronary infusion of 20 million C-kit positive human cardiac stem cells in pigs

Background

There is mounting interest in using c-kit positive human cardiac stem cells (c-kit^pos hCSCs) to repair infarcted myocardium in patients with ischemic cardiomyopathy. A recent phase I clinical trial (SCIPIO) has shown that intracoronary infusion of 1 million hCSCs is safe. Higher doses of CSCs may provide superior reparative ability; however, it is unknown if doses >1 million cells are safe. To address this issue, we examined the effects of 20 million hCSCs in pigs.

Methods

Right atrial appendage samples were obtained from patients undergoing cardiac surgery. The tissue was processed by an established protocol with eventual immunomagnetic sorting to obtain in vitro expanded hCSCs. A cumulative dose of 20 million cells was given intracoronarily to pigs without stop flow. Safety was assessed by measurement of serial biomarkers (cardiac: troponin I and CK-MB, renal: creatinine and BUN, and hepatic: AST, ALT, and alkaline phosphatase) and echocardiography pre- and post-infusion. hCSC retention 30 days after infusion was quantified by PCR for human genomic DNA. All personnel were blinded as to group assignment.

Results

Compared with vehicle-treated controls (n=5), pigs that received 20 million hCSCs (n=9) showed no significant change in cardiac function or end organ damage (assessed by organ specific biomarkers) that could be attributed to hCSCs (P>0.05 in all cases). No hCSCs could be detected in left ventricular samples 30 days after infusion.

Conclusions

Intracoronary infusion of 20 million c-kit positive hCSCs in pigs (equivalent to ~40 million hCSCs in humans) does not cause acute cardiac injury, impairment of cardiac function, or liver and renal injury. These results have immediate translational value and lay the groundwork for using doses of CSCs >1 million in future clinical trials. Further studies are needed to ascertain whether administration of >1 million hCSCs is associated with greater efficacy in patients with ischemic cardiomyopathy.

Early and midterm outcomes following surgery for acute type A aortic dissection

OBJECTIVE

Surgical repair of acute Type A aortic dissection (AADA) is still associated with high in-hospital mortality. We evaluated the impact of perioperative risk factors on early and midterm survival.

METHODS

Retrospective (2002-2011) database analysis at a single institution of 132 consecutive AADA patients (88 male, age 59.8 ± 13.6). All but five patients underwent repair with open distal anastomoses and hypothermic circulatory arrest: aortic valve replacement/root replacement (n=44, 33.3%) and valve re-suspension/repair (n=88, 66.7%). Ascending aorta, hemi-arch, and total arch repairs were performed in 11, 113, and eight patients, respectively. Antegrade and retrograde cerebral perfusion were used in all but six patients.

RESULTS

Overall in-hospital mortality was 17.4% (n=23). Actuarial survival at one, five, and eight years was 82%, 72%, and 62%, respectively. Perfusion time (cardiopulmonary bypass) (226.5 ± 71.3 vs. 177.5 ± 51.7, p=0.0002), aortic cross-clamp time (min) (132.8 ± 45.7 vs. 109.8 ± 41.2, p=0.01), aortic arch (T2) tear (31% vs. 14%, p=0.03), instability (26% vs. 11%, p=0.02), postoperative stroke (38% vs. 14%, p=0.009), and low cardiac output (50% vs. 15%, p=0.04) all correlated with increased perioperative mortality. A Cox proportional hazard model showed perfusion time (hazard ratio [HR]=1.01), postoperative stroke (HR=2.73), age (HR=1.03), and unstability (HR=1.8) as significant risk factors (p<0.05) affecting the overall survival.

CONCLUSION

There is a modern trend towards improving overall perioperative outcomes after surgical repair of AADA; however, early mortality and morbidity remain high even in aortic surgery referral centers.

Antegrade versus Retrograde Cerebral Protection in Repair of Acute Ascending Aortic Dissection

The objective of this study was to compare retrograde with antegrade cerebral protection during acute aortic dissection repair using cerebral oximetry measurements. Fifty consecutive acute ascending aortic dissection repairs were analyzed. Cerebral oximetry data were collected for 41 of 50. Eight patients who had antegrade cerebral protection alone and 29 of 41 had retrograde cerebral protection alone. The per cent change in cerebral oximetry values during deep hypothermic circulatory arrest from baseline and from prearrest values was compared for the two groups using Student t test. The per cent change from baseline for the antegrade patients was: right 13.8 per cent and left -2.5 per cent; the per cent change from baseline for retrograde patients was: right 0.8 per cent and left 0.2 per cent ( P values 0.216 and 0.725, respectively). The per cent change from the prearrest value for the antegrade patients was: right -12 per cent and left -15 per cent; the per cent change from prearrest for retrograde patients was: right -15 per cent and left -16 per cent ( P values 0.514 and 0.956, respectively). No compelling evidence for an advantage to either antegrade or retrograde cerebral perfusion was detected. Further study with a focus on neurologic outcomes is warranted.

Antegrade versus retrograde cerebral protection in repair of acute ascending aortic dissection

The objective of this study was to compare retrograde with antegrade cerebral protection during acute aortic dissection repair using cerebral oximetry measurements. Fifty consecutive acute ascending aortic dissection repairs were analyzed. Cerebral oximetry data were collected for 41 of 50. Eight patients who had antegrade cerebral protection alone and 29 of 41 had retrograde cerebral protection alone. The per cent change in cerebral oximetry values during deep hypothermic circulatory arrest from baseline and from prearrest values was compared for the two groups using Student t test. The per cent change from baseline for the antegrade patients was: right 13.8 per cent and left -2.5 per cent; the per cent change from baseline for retrograde patients was: right 0.8 per cent and left 0.2 per cent (P values 0.216 and 0.725, respectively). The per cent change from the prearrest value for the antegrade patients was: right -12 per cent and left -15 per cent; the per cent change from prearrest for retrograde patients was: right -15 per cent and left -16 per cent (P values 0.514 and 0.956, respectively). No compelling evidence for an advantage to either antegrade or retrograde cerebral perfusion was detected. Further study with a focus on neurologic outcomes is warranted.

Inflammatory aneurysms of the ascending aorta: diagnosis and surgical treatment

Inflammatory aortic aneurysms (IAAs) are rare and located mainly in the infra-renal abdominal aorta. The ascending aorta has been typically spared from this process. We report on two cases of ascending aortic inflammatory aneurysms and describe the available literature on this rare entity. 

Alternative surgical strategy for the treatment of a mycotic aortic arch aneurysm

We report the case of a 69-year-old man who presented with a symptomatic mycotic aneurysm of the aortic arch. Diagnosis was confirmed by positron emission tomography and by blood cultures positive for Salmonella species. A complete resection of the aortic arch process was performed via left thoracotomy using a cryopreserved aortic homograft and normothermic left heart bypass. The left-sided cerebral vessels were clamped, and adequacy of collateral left brain flow and oxygenation was confirmed by neurophysiologic monitoring. Using this less-invasive operative strategy, we avoided the risks inherent to deep hypothermic circulatory arrest and the use of prosthetic materials.

Memories of childhood abuse: dissociation, amnesia, and corroboration

OBJECTIVE

This study investigated the relationship between self-reported childhood abuse and dissociative symptoms and amnesia. The presence or absence of corroboration of recovered memories of childhood abuse was also studied.

METHOD

Participants were 90 female patients admitted to a unit specializing in the treatment of trauma-related disorders. Participants completed instruments that measured dissociative symptoms and elicited details concerning childhood physical abuse, sexual abuse, and witnessing abuse. Participants also underwent a structured interview that asked about amnesia for traumatic experiences, the circumstances of recovered memory, the role of suggestion in recovered memories, and independent corroboration of the memories.

RESULTS

Participants reporting any type of childhood abuse demonstrated elevated levels of dissociative symptoms that were significantly higher than those in subjects not reporting abuse. Higher dissociative symptoms were correlated with early age at onset of physical and sexual abuse and more frequent sexual abuse. A substantial proportion of participants with all types of abuse reported partial or complete amnesia for abuse memories. For physical and sexual abuse, early age at onset was correlated with greater levels of amnesia. Participants who reported recovering memories of abuse generally recalled these experiences while at home, alone, or with family or friends. Although some participants were in treatment at the time, very few were in therapy sessions during their first memory recovery. Suggestion was generally denied as a factor in memory recovery. A majority of participants were able to find strong corroboration of their recovered memories.

CONCLUSIONS

Childhood abuse, particularly chronic abuse beginning at early ages, is related to the development of high levels of dissociative symptoms including amnesia for abuse memories. This study strongly suggests that psychotherapy usually is not associated with memory recovery and that independent corroboration of recovered memories of abuse is often present.

Neurophysiologic monitoring to assure delivery of retrograde cerebral perfusion

BACKGROUND

Patients undergoing complex aortic procedures performed with deep hypothermia and circulatory arrest have a significant risk of an adverse neurologic event when the arrest period is prolonged. Retrograde cerebral perfusion appears to improve cerebral protection, although collapsed cortical veins or functional jugular venous valves may restrict flow at the frequently recommended maximum pressure of 25 mm Hg. Therefore, the purpose of this study was to demonstrate the benefit of multimodality neurophysiologic monitoring in assuring delivery of retrograde cerebral perfusion.

METHODS

Electroencephalography, cerebral blood flow velocity, and regional cerebral venous oxygen saturation were used to quantify the intraoperative neurophysiologic changes accompanying retrograde cerebral perfusion. The magnitude of changes was compared with those previously observed during arrest without retrograde cerebral perfusion.

RESULTS

Thirty patients underwent complex aortic procedures necessitating circulatory arrest, 22 with retrograde cerebral perfusion. The mean retrograde perfusion pressure of 40 mm Hg (30 to 49 mm Hg, 95% confidence interval) and flow rate of 1.2 L/min (0.9 to 1.6 L/min) necessary to achieve documented retrograde cerebral perfusion was much higher than previously recommended. During both retrograde cerebral perfusion and rewarming, cerebral oximetric monitoring guided adjustments in perfusion parameters to limit the rate of desaturation to 0.4% per minute (0.3% to 0.6%). With retrograde cerebral perfusion there was a rapid (1) recovery of electroencephalographic activity during rewarming (21 minutes [range 16 to 26 minutes]) and (2) return of consciousness after the operation (81% [58% to 95%, 95% confidence interval] awake by 12 hours). There was no transcranial Doppler evidence of cerebral edema with retrograde cerebral perfusion. Two neurologic complications occurred in the 22 patients managed with retrograde cerebral perfusion and one in the eight patients managed with arrest only.

CONCLUSIONS

Multimodality neurologic monitoring assured optimal brain cooling and bihemispheric delivery of retrograde cerebral perfusion. Necessary retrograde pressure and flow were often higher than values previously reported. Avoidance of profound cerebral venous oxygen desaturation during retrograde cerebral perfusion and rewarming was associated with rapid recovery of neurologic function.

The role of neuromonitoring in cardiovascular surgery

This review describes the techniques currently used for quantitative neurophysiologic measurement during cardiac surgery and their potential impact on clinical outcome. Electroencephalography (EEG) characterizes cerebrocortical neuronal electrical activity and was part of some of the earliest cardiopulmonary bypass procedures, yet today it is not widespread use. Each of the common misunderstandings regarding a supposed limitation of this technology is explained. Its major genuine shortcoming, a lack of selectivity, may now be overcome with the combined use of additional monitoring modalities. The influence of intracranial hemodynamics on observed EEG changes may be determined continuously and noninvasively with transcranial Doppler (TCD) ultrasound. TCD provides an indication of sudden change in either blood flow or vascular resistance as well as the detection of emboli. In addition, the metabolic status of cortical neurons can be monitored by regional cerebral venous oxygen saturation (rCVOS) using noninvasive transcranial near-infrared spectroscopy. The % rCVOS tends to remain remarkably stable over a wide range of temperatures, perfusion pressures, and anesthetic states. Marked change in either direction signifies a serious imbalance between oxygen delivery and consumption. Measurement of rCVOS does not require blood flow, pulsatile or otherwise, so that it offers the only means of monitoring during circulatory arrest. By characterizing the dynamic interplay among cerebral hemodynamics, metabolism, and electrogenesis, these technologies permit the rapid detection and correction of potentially hazardous conditions.

Retroperitoneal tumors with vena caval extension: a multidisciplinary approach

In cases of retroperitoneal tumor with extension to the inferior vena cava (IVC), complete resection improves survival, but may require cardiopulmonary bypass (CPB) and hypothermic circulatory arrest (HCA). Since 1985, eight patients at our institution have had complete resection of retroperitoneal tumors with IVC or right atrial involvement. Preoperative evaluation included intravenous pyelography, computed tomography of the chest and abdomen, renal arteriography, and venography or magnetic resonance imaging of the IVC. Operative technique was determined primarily by the extent of IVC or RA involvement and included combined median sternotomy and laparotomy, control of the intrapericardial IVC, and radical tumor resection. IVC tumor thrombectomy was done using either temporary vascular occlusion, CPB, or CPB with HCA. Complete resection for improved survival of retroperitoneal tumors with IVC extension is technically feasible with acceptable morbidity and mortality rates. A multidisciplinary approach allows optimal management of these extensive tumors.

Emergency aortocoronary bypass after failed angioplasty

One thousand two hundred fourteen percutaneous transluminal coronary angioplasties were performed over a 38-month period. Sixty patients required immediate emergency coronary artery bypass grafting after angioplasty failure; 7 of these had evidence of acute myocardial infarction before angioplasty and were excluded from the study. Of the 53 patients remaining, 27 (51%) had electrocardiographic and enzyme evidence of postoperative myocardial infarction. Two patients died (4%), and 10 had postoperative complications (19%). No statistical significance was noted comparing age, sex, incidence of prior myocardial infarction or myocardial dysfunction, time for revascularization, or average number of grafts completed in those with single-vessel (n = 21) versus multiple-vessel (n = 32) coronary artery disease. Postoperatively, those with multiple-vessel disease required intraaortic balloon pump support (p = 0.06) and antiarrhythmic medications more frequently than single-vessel patients (p less than 0.01) and had a higher complication rate (p less than 0.05). Although not reaching statistical significance, the data also suggest a higher death and postoperative myocardial infarction rate in patients with multiple-vessel disease. Emergency coronary artery bypass grafting after failed percutaneous transluminal coronary angioplasty carries a higher morbidity and mortality than elective coronary artery bypass grafting, particularly for patients with multiple-vessel coronary artery disease.

Repair of infected pseudoaneurysm with aortic arch replacement after orthotopic heart transplantation

Arterial wall infections are rare after orthotopic heart transplantation. An infected pseudoaneurysm developed in a patient at the site of aortic cannulation 6 months after his transplant procedure. Debridement of the infected tissue necessitated removal of a major portion of the aortic arch and reconstruction with in situ placement of a synthetic polyester (Dacron) graft. In situ placement of grafts is a controversial form of treatment of arterial wall infections in other portions of the aorta. Because of the extensive nature of the infection and its site, no other option was available. This patient represents the first reported case of successful aortic arch replacement for an infected pseudoaneurysm after orthotopic heart transplantation.

Surgical approach to atrial septal defect in the female. Right thoracotomy versus sternotomy

Repair of atrial septal defect (ASD) remains a high-benefit, low-risk procedure due to technologic improvements. From July 1981 to December 1986, 35 females (age, 7 months to 28 years) had repair of ASD; 20 by right thoracotomy and aortic cannulation (group 1) and fifteen by median sternotomy (group 2). In general, right thoracotomy was applied to patients with secundum ASD two years or older and without associated lesions, while median sternotomy was applied to patients with ostium primum lesions and/or associated lesions. Patients or their families perceived the cosmetic results superior to the right thoracotomy approach over the median sternotomy. We feel that a right thoracotomy and aortic cannulation is effective in females (2 years and older) with secundum ASD for a superior cosmetic result over median sternotomy. However, females with ostium primum and/or associated lesions should undergo median sternotomy for better cardiac access and safety.

A mediastinal liposarcoma: an illustrative approach to mediastinal tumors

Mediastinal masses remain an interesting diagnostic and therapeutic challenge for clinicians because of the low incidence of the tumors, frequent lack of symptoms, and the inaccessibility of the tumors for biopsy. An unusual mediastinal liposarcoma with intracavitary cardiac extension is presented to illustrate the approach to mediastinal tumors in general.

The Pierce-Donachy ventricular assist device as a bridge to cardiac transplantation

The Pierce-Donachy ventricular assist device (VAD) was used as an attempted bridge to orthotopic cardiac transplantation in 12 patients aged 13 to 55 years. Ischemic (4 patients), dilated (4 patients), acute viral (1 patient), postpartum (1 patient), and hypertrophic cardiomyopathy (1 patient), along with a failed transplant (1 patient), were the causative factors of end-stage cardiomyopathy in these patients. All patients were candidates for orthotopic cardiac transplantation but sustained refractory cardiogenic shock (cardiac index less than 2 L/min/m2). Left VADs were placed in all patients; 7 also required right VADs. Four patients died of hemorrhagic complications less than 24 hours after VAD insertion. Ventricular assist device stabilization was successful in 8 patients and support ranged from eight hours to 64 days. Seven patients successfully underwent orthotopic cardiac transplantation. One died postoperatively of hemorrhagic complications, 6 were discharged from the hospital, and 1 patient died at 3 months of cytomegalovirus infection. Five patients are long-term survivors. The Pierce-Donachy VAD is an effective means for supporting critically ill patients with end-stage cardiomyopathy and cardiogenic shock before orthotopic cardiac transplantation. Death is related to hemorrhagic, rather than infectious or thromboembolic, complications. Patients successfully stabilized with the VAD can undergo orthotopic cardiac transplantation with acceptable mortality and morbidity rates.

Treatment of malignant ventricular arrhythmias with the automatic implantable cardioverter defibrillator

Twenty-eight patients with malignant ventricular arrhythmias were treated with the automatic implantable cardioverter-defibrillator (AICD) in a 14-month period. Thirteen patients were resuscitated from a ventricular fibrillation (VF) episode. Fifteen patients presented with ventricular tachycardia (VT) refractory to medical therapy. The etiology was coronary artery disease in 23 of 28 patients (82%), dilated cardiomyopathy in 2 of 28 patients (7%), sarcoidosis in 2 of 28 patients, and 1 patient in 28 had lupus erythmatosis. The mean left ventricular ejection fraction was 29%. A total of 27 of 28 patients (96%) patients had inducible ventricular tachycardia using programmed stimulation. The patients considered for AICD implant failed a mean of 3.6 antiarrhythmic drugs. Rate counting and defibrillating leads were inserted through a lateral thoracotomy in 17 patients and a mediansternotomy incision in 11 patients in conjunction with another cardiac procedure in 10 patients. The generators were positioned in a subcutaneous pocket beneath the left costal margin. There were no operative deaths. The mean follow-up was 6.7 months (range 1 to 14) with no VT/VF deaths in patients with defibrillators. The study demonstrated that AICD is an effective device for prevention of sudden cardiac death.

Otolaryngologic problems in cardiac transplant patients

Cardiac transplantation is now a well-accepted treatment for selected patients who have end-stage heart disease. Of the 38 patients who underwent cardiac transplants at our center from August 1984 through August 1987, 27 received consultation for otolaryngologic problems. Eleven patients had sinonasal complications; 8 had laryngotracheal complications; 4 had otologic complications; 2 had oropharyngeal complications; and 2 had a combination of more than one of the above complications. Of these otolaryngologic disorders, 63% were infectious in etiology. Development of otolaryngologic infections generally did not correlate with either higher doses of maintenance immunosuppression or with treatment of an acute rejection episode, which requires increased immunosuppression. Otolaryngologists should be aware of the sinonasal, laryngotracheal, oropharyngeal, and otologic disorders that can occur in cardiac transplant patients.

Surgical techniques for the implantation of heterotopic prosthetic ventricles

Mechanical support of the failing heart is becoming an increasingly useful tool for bridging to cardiac transplantation and for recovery of the natural heart. Several options exist for cannulation sites during the implantation of the heterotopic prosthetic ventricles. These options include the left atrial appendage, the left ventricular apex, the interatrial groove, and the left atrial roof. The indications, contraindications, advantages, disadvantages, and surgical technique for each option are described. Operation of the drive console and postoperative care are also discussed.

Infant orthotopic cardiac transplantation

Infant orthotopic cardiac transplantation has been recently applied to various forms of congenital heart disease with encouraging short-term results. Between June 1986 and September 1987 we evaluated 16 infants for orthotopic cardiac transplantation. Fourteen had hypoplastic left heart syndrome, one had endocardial fibroelastosis with aortic atresia, and one had anomalous pulmonary arterial origin of the left main coronary. Eight families accepted the treatment program and eight families refused (two because of associated anomalies and six on philosophical grounds). Of the eight patients who were candidates for orthotopic cardiac transplantation, one died 6 hours after diagnosis, one was allowed to die after 60 days because of acquired neurologic complications, and another had congenital cytomegalic virus infection. The remaining five patients (four with hypoplastic left heart syndrome, one with anomalous pulmonary arterial origin of the left main coronary) had orthotopic cardiac transplantation. The operation was performed with absorbable polydioxanone suture with deep hypothermia and circulatory arrest in four neonates for hypoplastic left heart syndrome (average time 47 minutes) and bicaval cannulation and continuous bypass in one 11-month-old infant for anomalous origin of the left main coronary. In-house retrieval was used in all. One neonate died of complications as a result of pretransplant donor heart dysfunction and size discrepancy, whereas the remaining three neonates and one infant survived and are home 23 months, 12 months, and 8 months (the patients with hypoplastic left heart syndrome) and 17 months (the patient with anomalous origin of the left main coronary) postoperatively. Triple-drug immunosuppression included cyclosporine, azathioprine, and prednisone. Rejection was diagnosed by clinical evaluation of child activity and monocyte cell cycle analysis from peripheral blood samples without myocardial biopsies. Routine echocardiograms, electrocardiograms, and chest x-ray films were not helpful. Six episodes of rejection were successfully treated in four patients. Twelve-month postoperative catherization in one patient (hypoplastic left heart syndrome) showed appropriate graft growth, no aortic or pulmonary anastomotic strictures, normal right and left ventricular function, and no coronary artery disease. We conclude that infant orthotopic cardiac transplantation is an acceptable procedure for severe forms of untreatable congenital heart disease. The excellent short-term results warrant continued application of orthotopic cardiac transplantation.

Successful treatment of empyema thoracis with polymethylmethacrylate antibiotic-impregnated beads in the guinea pig

Two hundred nine Duncan-Harley guinea pigs had intrathoracic inoculation with 10(8) Staphylococcus aureus, accompanied by blood and umbilical tape. One hundred fifty-two animals were excluded because of clinical recovery, early death, or complications related to intrathoracic polymethylmethacrylate (PMMA) bead placement. The remaining 57 animals had clinical signs of empyema thoracis and were the subjects of this study. Group I animals (N = 24) served as the controls and had no therapy. Group II animals (N = 14) were treated by intrathoracic placement of placebo PMMA beads. Group III animals (N = 19) were treated by intrathoracic placement of tobramycin sulfate-impregnated PMMA beads. There were no differences between the groups in pleural reaction or pneumonia scores. These findings demonstrate a similar host response to the established infection. Group III, however, had a higher sterilization rate than Groups I and II (p less than 0.05), a finding underlining the therapeutic effect of tobramycin-treated PMMA beads. We conclude that intrathoracic local antimicrobial therapy with slow-release tobramycin-impregnated PMMA beads may enhance empyema treatment by increasing the rate of local sterilization. More experiments are necessary to assess the efficacy of this potentially important therapeutic arm for the treatment of thoracic empyema.

Myocardial preservation in the neonate. Beneficial effects of cardioplegia and systemic hypothermia on piglets undergoing cardiopulmonary bypass and myocardial ischemia

This study examined anatomic differences between the adult and the newborn heart as they relate to myocardial preservation and compared standard techniques of myocardial preservation used in operations for congenital heart disease. The biventricular endocardial surface area/ventricular mass ratios were calculated in 10 neonatal (2.5 +/- 0.2:1) and 10 adult (0.6 +/- 0.1:1) pigs (p less than 0.001). Three groups of neonatal pigs underwent 1 hour of global myocardial ischemia while being supported by cardiopulmonary bypass. Myocardial protection was by deep systemic hypothermia (group 1), moderate systemic hypothermia and cardioplegia (group 2), or by deep systemic hypothermia and cardioplegia (group 3). Left ventricular end-systolic pressure-dimension and end-diastolic pressure-dimension relationships were measured before and after cardiopulmonary bypass. Septal temperatures remained below 20 degrees C in groups 1 and 3 but rose above 20 degrees C in group 2. Groups 1 and 2 had moderate and mild ventricular stiffening, respectively, whereas group 3 showed no diastolic dysfunction. Ventricular contractility was increased (p less than 0.05) in group 3. Techniques for myocardial preservation used during operations for congenital heart disease must consider the large endocardial surface area/mass ratio and the rewarming effects of systemic blood. The combination of deep systemic hypothermia and cardioplegia provided superior myocardial protection compared with the other techniques tested.

Use of OKT3 monoclonal antibody in the treatment of acute cardiac allograft rejection

OKT3 is a murine monoclonal antibody that recognizes the T3 surface antigen present on mature T cells, and it has been used to successfully treat renal allograft rejection. We report our experience with OKT3 in the treatment of cardiac allograft rejection. Eight patients with endomyocardial biopsy evidence of moderate or severe rejection were given fourteen daily intravenous treatments of OKT3. Six of the eight patients had complete recovery following OKT3 therapy; one required additional steroid therapy for recurrence and one patient failed to respond. Five of the six patients with a complete response have experienced no further rejection (mean follow-up 437 days). Adverse reactions to OKT3 were common early in the treatment course, but were well tolerated. We concluded that OKT3 is a safe and effective treatment of cardiac allograft rejection and that a majority of patients experience long-term rejection-free periods.

Experimental aerobic-anaerobic thoracic empyema in the guinea pig

The clinical and pathological features of experimental aerobic-anaerobic thoracic empyema in the Duncan-Harley guinea pig are described. Thoracic empyema development and early death (less than 14 days after bacterial inoculation) were noted after various concentrations and species were inoculated into the pleural space with a piece of umbilical tape, which was used as a cofactor. The effect of concomitant hemothorax was also tested. Gram-negative infection was found to have a more virulent course than Gram-positive infection in the thoracic cavity. Moreover, these findings support the thesis that intrathoracic inoculation of anaerobic bacteria, even in combination with other anaerobic species, fails to produce clinical empyemas. However, anaerobic bacteria appear to enhance synergistically the virulence of sublethal and subempyema-forming concentrations of aerobic bacteria such as Staphylococcus aureus and Escherichia coli.

Effect of hemothorax on experimental empyema thoracis in the guinea pig

An experimental model for empyema thoracis in the Duncan-Harley guinea pig is introduced. Empyema thoracis development and early death (less than 14 days after bacterial inoculation) were noted after various concentrations and species were inoculated into the pleural space with a piece of umbilical tape, which was used as a cofactor. The effect of concomitant hemothorax was also tested. Group I (N = 90) had intrapleural inoculation of umbilical tape and various concentrations (10(4), 10(6), 10(8) organisms/ml) of various bacterial species, which included Staphylococcus aureus (N = 30), Escherichia coli (N = 30), and Bacteroides fragilis (N = 30). Group II (N = 90) had intrapleural inoculation of umbilical tape, 1 ml of autologous blood, and the same varying concentrations and species of bacteria as Group I. The observation period was 14 days, during which time early deaths were noted. Fifty-eight percent of the staphylococcal group of animals, 37% of the E. coli group of animals, and none of the B. fragilis group of animals developed empyema. Animals with empyema developed significant weight loss (p less than 0.05) and roentgenographic evidence of empyema, which was supported by postmortem pleural reaction and pneumonia scores (p less than 0.05). Higher concentrations of inoculated bacteria produced a higher incidence of empyema in the S. aureus and E. coli groups (p less than 0.05), but concomitant hemothorax did not increase the already high incidence of empyema and early death in the E. coli group. Empyema caused by B. fragilis did not develop, even with cofactors of umbilical tape and blood. Anaerobic infections in this model may require the presence of other aerobic or facultative organisms, the presence of necrotic lung, prior malnutrition, or a combination thereof.