We present our experience with an alternative technique for orthotopic heart transplantation. It consists of total excision of the recipient's atria, with the donor's heart implantation performed ...using bicaval end-to-end anastomoses as well as pulmonary venous anastomoses. Forty consecutive patients receiving transplants in this fashion were compared with 64 patients who underwent orthotopic transplantation with the standard technique. The incidence of postoperative tricuspid regurgitation was reduced in patients receiving transplants with the new surgical approach (
p = 0.003). In addition, the need for pacemaker implantation for severe bradyarrhythmia in the early (0 to 6 weeks) posttransplantation period (
p = 0.003) was eliminated. Although not statistically significant, there was a trend in the reduction of postoperative mitral regurgitation in patients who received transplants by the modified technique. Based on this experience, we believe this modified technique for orthotopic heart transplantation has an anatomic and physiologic advantage that may improve long-term hemodynamic results.
OBJECTIVES
This study was done to determine whether electrocardiographic (ECG) isolated ST-segment elevation (ST↑) in posterior chest leads can establish the diagnosis of acute posterior infarction ...in patients with ischemic chest pain and to describe the clinical and echocardiographic characteristics of these patients.
BACKGROUND
The absence of ST↑ on the standard 12-lead ECG in many patients with acute posterior infarction hampers the early diagnosis of these infarcts and thus may result in inadequate triage and treatment. Although 4% of all acute myocardial infarction (AMI) patients reveal the presence of isolated ST↑ in posterior chest leads, the significance of this finding has not yet been determined.
METHODS
We studied 33 consecutive patients with ischemic chest pain suggestive of AMI without ST↑ in the standard ECG who had isolated ST↑ in posterior chest leads V7through V9. All patients had echocardiographic imaging within 48 h of admission, and 20 patients underwent coronary angiography.
RESULTS
Acute myocardial infarction was confirmed enzymatically in all patients and on discharge ECG pathologic Q-waves appeared in leads V7through V9in 75% of the patients. On echocardiography, posterior wall-motion abnormality was visible in 97% of the patients, and 69% had evidence of mitral regurgitation (MR), which was moderate or severe in one-third of the patients. Four patients (12%), all with significant MR, had heart failure, and one died from free-wall rupture. The circumflex coronary artery was the infarct related artery in all catheterized patients.
CONCLUSIONS
Isolated ST↑ in leads V7through V9identify patients with acute posterior wall myocardial infarction. Early identification of those patients is important for adequate triage and treatment of patients with ischemic chest pain without ST↑ on standard 12-lead ECG.
We hypothesized that orthotopic heart transplantation with bicaval and pulmonary venous anastomoses preserves atrial contractility.
The standard biatrial anastomotic technique of orthotopic heart ...transplantation causes impaired function and enlargement of the atria. Cine magnetic resonance imaging (MRI) allows assessment of atrial size and function.
We studied 16 patients who had undergone bicaval (n = 8) or biatrial (n = 8) orthotopic heart transplantation without evidence of rejection and a control group of 6 healthy volunteers. For all three groups, cine MRI was performed by combining coronal and axial gated spin echo and gradient echo cine sequences. Intracardiac volumes were calculated with the Simpson rule. Atrial emptying fraction was defined as the difference between atrial diastolic and systolic volumes, divided by atrial diastolic volume, expressed in percent. All patients had right heart catheterization.
Right atrial emptying fraction was significantly higher in the bicaval (mean ±SD 37 ± 9%) than in the biatrial group (22 ± 11%, p < 0.05) and similar to that in the control group (48 ± 4%). Left atrial emptying fraction was significantly higher in the bicaval (30 ± 5%) than in the biatrial group (15 ± 4%, p < 0.05) and significantly lower in both transplant groups than in the control group (47 ± 5%, p < 0.05). The left atrium was larger in the biatrial than in the control group (p < 0.05). Cardiac index, stroke index, heart rate and blood pressure were similar in the transplant groups.
Left and right atrial emptying fractions are significantly depressed with the biatrial technique and markedly improved with the bicaval technique of orthotopic heart transplantation. The beneficial effects of the latter technique on atrial function could improve allograft exercise performance.
OBJECTIVE: Pretransplant pulmonary vascular resistance > or = 4 Wood-units predisposes to right ventricular failure after heart transplantation.Total orthotopic heart transplantation with bicaval and ...pulmonary venousanastomoses offers synchronous contractions of the atria and a normalventricular filling pattern, but requires longer ischemic time thanstandard orthotopic heart transplantation. To test if total orthotopicheart transplantation improves resting hemodynamics in pts with highpreoperative pulmonary vascular resistance, we analyzed 65 pts withstandard and 65 with total orthotopic heart transplantation transplantedbetween 12/88 and 7/94. Of these, 18 with total and 15 with standardorthotopic heart transplantation had a preoperative pulmonary vascularresistance > or = 4 Wood-units. METHODS: Right heart catheterizationdata were obtained at each endomyocardial biopsy. All data from biopsies atboth 2 weeks and 1 year posttransplant that were free from humoral orgreater than 1A cellular rejection (9 versus 13 pts) were included in a twoway ANOVA. Pts with postop pacemakers, atrial fib or beta-blocker therapyat the time of biopsy were excluded. RESULTS: Ischemic time was different(172 +/- 44 versus 142 +/- 28 min, P = 0.03). Demographics, NYHA class,pre- TX hemodynamics, donor age and inotropes were similar. Cardiac outputand index were higher in the total orthotopic group at 2 weeks (6.5 +/- 1.7versus 5.1 +/- 1.0 l/min; 3.4 +/- 0.9 versus 2.8 +/- 0.6 l/min per m2) and1 year (7.1 +/- 2.0 versus 4.9 +/- 1.1 l/min, P = 0.002; 3.6 +/- 1.1 versus2.6 +/- 0.5 l/min per m2, P = 0.009). Right atrial and pulmonary arterialmean pressure (mmHg) were lower with total orthotopic heart transplantationat 2 weeks (6 +/- 4 versus 9 +/- 5, P = 0.04; 22 +/- 3 versus 25 +/- 7, P =0.1) and 1 year (5 +/- 2 versus 7 +/- 3, P = 0.02; 19 +/- 4 versus 25 +/-7, P = 0.03). Pulmonary capillary wedge pressure (mmHg) was borderlinenonsignificant (11 +/- 4 versus 13 +/- 7 at 2 weeks, 8 +/- 3 versus 14 +/-5 at 1 year, P = 0.055), as well as pulmonary vascular resistance (1.9 +/-1 versus 2.5 +/- 1 at 2 weeks, 1.5 +/- 0.6 versus 2.7 +/- 1.7 WU at 1 year,P = 0.051). CONCLUSIONS: Total orthotopic heart transplantation improvescardiac output and index in pts with high preoperative pulmonary vacularresistance. There is a lower mean RA and PA pressure perhaps due to lesstricuspid and mitral regurgitation. In view of the frequently observedrestrictive filling pattern after cardiac transplantation, total orthotopicheart transplantation can be beneficial until this pattern has subsided bypreserving atrioventricular synchrony and offering better atrialtransport.
Orthotopic heart transplantation (OHT) with bicaval and pulmonary venous anastomoses avoids the large atrial anastomoses of the standard biatrial technique. To determine whether the bicaval technique ...improves atrial performance, we used Doppler echocardiography to study 13 patients with bicaval OHT, 15 with biatrial OHT, and 8 normal subjects. All were in sinus rhythm and free of rejection. Left atrial size, transmitral (M) and late diastolic (A) mitral flow velocity integrals were measured. Atrial transport (A/M, %) and atrial ejection force (kilodynes, calculated from peak A-wave velocity and mitral orifice area) were assessed. Left atrial dimensions in the bicaval (4.3 ± 0.5 cm) and biatrial groups (4.9 ± 0.9 cm) were larger than in controls (3.3 ± 0.8 cm,
p < 0.05). Left atrial transport (37% ± 12% and 35% ± 12%) and ejection force (14.1 ± 6.9 kdyne and 10.2 ± 7.8 kdyne) were similar in the bicaval group and controls (
p not significant) but were significantly lower in the biatrial group (20% ± 19% and 3.6 ± 4.0 kdynes,
p < 0.05). The bicaval and pulmonary venous technique of OHT produces more physiologic atrial function compared with the biatrial technique as evidenced by greater atrial ejection force and more normal atrial transport.
Scarcity of suitable donor organs remains a major problem for organ transplantation. Transfer of recipient HLA-genes into animal donor-organs during harvest could induce graft-tolerance without ...suppressing the recipient immune system. OBJECTIVE: This pilot study aimed to test the feasibility of an in vivo gene transfer into pig hearts by intracoronary infusion of DNA: liposome-complexes and to detect the gene product by immunohistochemistry. METHODS: The pcDV1-pL2-vector, containing the basesequence for HLA-DR alpha-chain in plasmids (1.3 kb) was selected. The plasmids were isolated with ethidium bromide and incubated with lipofectinin a 1:3-ratio for 10 min. The DNA:lipofectin-complex was diluted to 10 ccwith physiologic saline and delivered into the left anterior descending artery of 6 farm pigs over 10 min. As a control within the same animal, the same amount of lipofectin alone was infused into the first diagonal branch .Three pigs were sacrificed after 24 h, the other 3 after 48 h. Delivery of DNA:liposome-complexes was detected by oil red 0 staining, expression of HLA-DR alpha-chain-antigen with a monoclonal anti-HLA-DR alpha-antibody. RESULTS: Transfection of the HLA-class-II DR-alpha-chain occurred inendothelial cells. Infiltrating cells around capillaries stained positively for HLA-DR-alpha. These infiltrating cells were negative for the pan B-and the pan T-cell-marker L26 and UCHL-1. There was no transfection and hypercellularity in the myocardium around the first diagonal branch. CONCLUSIONS: In vivo intracoronary infusion of the HLA-DR alpha-chain-DNA:lipofectin-complex leads to expression of the corresponding antigen onpig endothelium for 48 h. The infiltrating cells require further characterization.
The beneficial effect of aspirin (ASA) in unstable angina is well established, yet data on effect of ASA during the hyperacute phase of myocardial infarction (AMI) is limited. We evaluated the effect ...of early chewed ASA administration on reperfusion rate and hospital outcome in 90 consecutive AMI patients treated at home or in the Emergency Room. All patients had ischemic chest pain of ≥30minutes, associated with ≥2mm ST↑. Early reperfusion within 30 minutes occurred in 42 patients (46.7%); only 3 patients needed thrombolysis. In 27 controls reperfusion occurred in 7 patients (25.9%); p=0.05. No difference in hospital outcome was observed between patients with ASA-induced reperfusion and patients treated by thrombolytics.
1) Chewed ASA taken early in the hyperacute phase of AMI induced sustained reperfusion in a significant number of patients (46.7%); 2) The above results call for on-scene early administration of chewed ASA in all suspected AMI patients.
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