RESUMO
The natural history of patients with ischemic cardiomyopathy, asymptomatic nonsustained ventricular tachycardia, and negative electrophysiologic studies was assessed in a retrospective analysis of 55 consecutive patients. The results suggest that the prognosis for arrhythmic death in these patients is not necessarily benign.
Assuntos
Estimulação Cardíaca Artificial/métodos , Cardiomiopatias/complicações , Cardiomiopatias/diagnóstico , Morte Súbita Cardíaca/etiologia , Eletrocardiografia/métodos , Isquemia Miocárdica/complicações , Isquemia Miocárdica/diagnóstico , Taquicardia Ventricular/complicações , Taquicardia Ventricular/diagnóstico , Idoso , Análise de Variância , Cardiomiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Taquicardia Ventricular/classificação , Taquicardia Ventricular/fisiopatologia , Fatores de Tempo , Função Ventricular EsquerdaRESUMO
Left ventricular (LV) ejection fraction may not adequately detect a reduction in LV systolic performance resulting from chronic mitral regurgitation (MR), due to ventricular unloading into the low-impedance left atrium. To determine whether LV ejection fraction sufficiently gauges myocardial function in MR, nine patients were studied using micromanometer-measured LV pressures and biplane cineventriculography before and 1 year after mitral valve surgery. Six control patients were also studied. LV ejection fraction was normal in MR patients, despite an increase in LV end-systolic volume index. LV end-systolic pressure-volume and stress-volume ratios in MR patients were lower than in controls (P < 0.05 and P < 0.01), suggesting that LV systolic performance fell. One year after mitral valve surgery, LV ejection fraction decreased (P < 0.05) even though LV end-systolic volume index (P < 0.05), pressure-volume (P < 0.05), and stress-volume ratios (P < 0.01) all improved. Thus, LV ejection fraction inadequately reflected LV systolic function in MR patients before and after mitral valve surgery.
Assuntos
Insuficiência da Valva Mitral/fisiopatologia , Contração Miocárdica , Volume Sistólico , Função Ventricular Esquerda , Doença Crônica , Hemodinâmica , Humanos , Masculino , Sístole/fisiologiaRESUMO
The process of thoracic surgery resident education is and always has been taken very seriously at the University of Michigan, where it is regarded as a key mission of the faculty. More attention is paid to the details of providing a supportive educational environment using established principles of education, curriculum planning, evaluation, and feedback. Resident education is the order of business today and, although challenged by the demands of managed care and cost containment, it remains among the most important priorities at the University of Michigan.
Assuntos
Faculdades de Medicina/história , Cirurgia Torácica/história , História do Século XX , Humanos , MichiganRESUMO
BACKGROUND: Perioperative administration of intravenous diltiazem to patients undergoing cardiac procedures has been shown to decrease the incidence of ischemia and arrhythmias. However, after adopting this practice in our cardiac surgery program, we perceived an increased incidence of postoperative renal dysfunction. METHODS: A directed record review of postoperative renal function was conducted for consecutive patients undergoing cardiac operation for the time periods before and after adoption of prophylactic intravenous diltiazem (0.1 mg.kg-1.h-1 for 24 hours). The two groups were compared using chi 2 and two-sample t tests. The risk of development of postoperative renal failure was modeled with logistic regression. RESULTS: Diltiazem-treated patients (n = 271) were similar to the control patients (n = 143) in terms of age (64 versus 61 years; p = 0.14), ejection fraction (0.46 versus 0.47; p = 0.61), baseline serum creatinine level (1.2 versus 1.1 mg/dL; p = 0.27), prevalence of comorbid conditions, and surgical characteristics. The prevalence of left main coronary artery disease was lower in the diltiazem group than the control group (39% versus 52%; p = 0.01). During the 7-day postoperative period, the average peak serum creatinine level was higher in the diltiazem group (1.7 +/- 0.9 mg/dL; mean +/- 1 standard deviation) than the control group (1.5 +/- 0.5 mg/dL; p = 0.003). The incidence of acute renal failure requiring dialysis was 4.4% in the diltiazem group versus 0.7% in the control group (p = 0.04). There was no difference in length of hospitalization or mortality. The risk of acute renal failure was strongly associated with intravenous diltiazem (adjusted odds ratio [AOR] 6.3; p = 0.08), age (AOR 2.5 per 10 years; p = 0.07), baseline serum creatinine (AOR 4.8 per 1 mg/dL; p = 0.02), the presence of left main coronary disease (AOR 5.3; p = 0.02), and the presence of cerebrovascular disease (AOR 4.5; p = 0.05). CONCLUSIONS: Our retrospective analysis suggests that prophylactic use of intravenous diltiazem in patients undergoing cardiac operations was associated with increased renal dysfunction. Further studies of the risk and benefits of intravenous diltiazem in this setting should be undertaken.
Assuntos
Injúria Renal Aguda/etiologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Ponte de Artéria Coronária , Diltiazem/uso terapêutico , Vasodilatadores/uso terapêutico , Injúria Renal Aguda/terapia , Fatores Etários , Arritmias Cardíacas/prevenção & controle , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Transtornos Cerebrovasculares/complicações , Distribuição de Qui-Quadrado , Ponte de Artéria Coronária/efeitos adversos , Doença das Coronárias/cirurgia , Creatinina/sangue , Diltiazem/administração & dosagem , Diltiazem/efeitos adversos , Feminino , Humanos , Incidência , Infusões Intravenosas , Cuidados Intraoperatórios , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/prevenção & controle , Razão de Chances , Prevalência , Diálise Renal , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversosRESUMO
Previous studies have reported a significant morbidity and mortality associated with coronary artery bypass graft (CABG) surgery in conjunction with the placement of an implantable cardioverter defibrillator (ICD) with an epicardial lead system. In the absence of a control group, how significantly the component of concomitant placement of the ICD system contributes to these untoward outcomes remains unknown. The purpose of this study was to assess the short- and long-term complications in patients undergoing CABG surgery in conjunction with the placement of an ICD with epicardial leads and to compare these complications with those of patients who had only CABG surgery (control group). The study group (group A) consisted of 56 patients who underwent CABG surgery and placement of an ICD pulse generator with epicardial leads. A control group (group B) consisted of 56 patients who underwent CABG surgery only during the same time period. The two groups were matched for age, sex distribution, left ventricular function, surgical approach, number of bypass grafts per patient, bypass pump time, and length of follow-up period. The early mortality for group A was 7.1% versus 1.8% for group B (p > 0.05). The incidence of early morbidity (congestive heart failure, infection, supraventricular and ventricular arrhythmias) for groups A and B was similar (26.8% vs 25.0%, p > 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Ponte de Artéria Coronária , Desfibriladores Implantáveis , Complicações Pós-Operatórias , Idoso , Arritmias Cardíacas/mortalidade , Estudos de Casos e Controles , Ponte de Artéria Coronária/mortalidade , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de TempoRESUMO
Primary amyloidoma of the chest wall presents as an aggressive tumor that causes local destruction. It is best treated with wide local excision and reconstruction as required, which usually is curative. A search for occult systemic disease also is recommended.
Assuntos
Amiloidose/diagnóstico , Neoplasias Torácicas/diagnóstico , Amiloidose/cirurgia , Biópsia por Agulha , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Torácicas/cirurgia , Tomografia Computadorizada por Raios XRESUMO
Recognition of tachyarrhythmia by an implantable cardioverter-defibrillator (ICD) requires an intact rate-sensing lead. We retrospectively examined 266 consecutive patients requiring an ICD to characterize the incidence, clinical presentation, diagnosis, and management of a defective rate-sensing lead. To identify clinical parameters that may contribute to lead complications, we also assessed the effects of age, gender, type of rate-sensing lead, manufacturer of the lead, and surgeon. Over a follow-up period of 30 +/- 22 months (mean +/- standard deviation), a defective lead was found in 9 (3.4%) patients, in 9 (1.7%) of 514 leads over a period of 2 to 39 (mean 17 +/- 15) months after implantation. Except for 1 patient, in whom a lead fracture was incidently found during ICD generator replacement, these patients had multiple inappropriate shocks of recent onset. Clinical parameters were not helpful in identifying patients at risk for lead complication. An abnormal beeping signal obtained while the patients performed various maneuvers was helpful in confirming a defect. All of the defective leads were epicardial. These cases were managed by placement of a transvenous endocardial lead.
Assuntos
Desfibriladores Implantáveis , Eletrodos Implantados , Falha de Equipamento/estatística & dados numéricos , Feminino , Seguimentos , Parada Cardíaca/terapia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia Ventricular/terapia , Fatores de Tempo , Fibrilação Ventricular/terapiaRESUMO
BACKGROUND: Imaging of myocardial glucose metabolism using [18F]fluorodeoxyglucose (FDG) with positron emission tomography (PET) has been proposed for identification of tissue viability in patients with advanced coronary artery disease. This study was designed to evaluate the predictive value of flow and metabolic imaging for functional recovery after revascularization in myocardial segments of varying degrees of dysfunction. METHODS AND RESULTS: Thirty-seven patients (mean age, 59 +/- 11 years) with coronary artery disease and impaired left ventricular function (ejection fraction, 34 +/- 10%) were studied with PET using FDG and [13N]ammonia before surgical coronary revascularization (3 +/- 1 grafts per patient). Tissue was scintigraphically characterized as normal, nonviable (concordant reduction of perfusion and FDG uptake), viable without discordance of perfusion and metabolism (mildly reduced perfusion and metabolism), or ischemically compromised (mismatch of reduced perfusion and maintained FDG uptake). Functional outcome was assessed by serial radionuclide ventriculography before and at 13 +/- 13 weeks (median interval of 8 weeks) after coronary revascularization. Preoperatively impaired regional wall motion improved significantly in ischemically compromised (mismatch) revascularized segments but not in nonviable myocardium or in viable myocardium without discordance of perfusion and metabolism. The negative predictive value of PET for functional recovery was 86%, whereas the positive predictive value in revascularized regions ranged from 48% to 86% depending on severity of baseline wall motion abnormalities. CONCLUSIONS: PET identifies metabolically active tissue, which benefits from revascularization. Although the negative predictive value of PET for recovery was high, functional improvement of viable but ischemically compromised tissue was less frequent than previously reported. The predictive value of PET was highest in left ventricular segments with severe dysfunction and a mismatch or reduced perfusion but preserved metabolism. Integration of PET, angiographic, and functional data is necessary for the optimal selection of patients with advanced coronary artery disease and impaired left ventricular function for revascularization.
Assuntos
Doença das Coronárias/fisiopatologia , Glucose/metabolismo , Revascularização Miocárdica , Miocárdio/metabolismo , Adulto , Idoso , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perfusão , Tomografia Computadorizada de Emissão , Função Ventricular EsquerdaRESUMO
Since 1980, the automatic implantable cardioverter defibrillator (ICD) has evolved as effective therapy for prevention of sudden cardiac death following documented sustained ventricular tachycardia or fibrillation. During a 5-year period, 412 ICD devices were implanted at the University of Michigan Hospitals with a wound complication rate of 4.1%. In this group, there were 13 infections, 3 erosions of the generator pocket, and 1 wound hematoma. Of the 16 patients with infection or erosion, 12 patients were treated with a rectus abdominis muscle flap closure and 4 with ICD generator removal. In 83% (n = 12) of the muscle flap patients, the wound healed uneventfully. Preoperative chest CT scanning was found to be helpful in identifying probable infection of the epicardial leads. In these cases, all hardware had to be removed to achieve resolution of the infection. We concluded that rectus abdominis muscle flaps were helpful in salvaging infected or exposed ICD generators in the absence of infected epicardial leads.
Assuntos
Desfibriladores Implantáveis/efeitos adversos , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Infecções Bacterianas/terapia , Humanos , Pessoa de Meia-Idade , Reoperação , Infecção da Ferida Cirúrgica/microbiologia , Taquicardia Ventricular/terapia , Tomografia Computadorizada por Raios X , Fibrilação Ventricular/terapiaRESUMO
OBJECTIVES: We tested the hypotheses that left ventricular chamber elastance would detect impaired contractile function in patients with long-term mitral regurgitation and a normal ejection fraction and that these patients would have unique temporal left ventricular size and ejection fraction responses to mitral valve surgery. BACKGROUND: Although it has been suggested that left ventricular contractile function may begin deteriorating in patients with long-term mitral regurgitation whereas ejection fraction remains normal, no data exist in humans. METHODS: We studied 11 control patients and 28 patients with long-term mitral regurgitation using micromanometer-measured pressures, biplane contrast cineventriculography and radionuclide angiography under control conditions and with alterations in load during right atrial pacing to calculate left ventricular chamber elastance and myocardial stiffness. RESULTS: The patients with mitral regurgitation were classified into subgroups: Group I, normal contractile function; Group II, impaired contractile function (reduced Emax) but normal ejection fraction, and Group III, impaired contractile function (reduced Emax) with reduced systolic myocardial stiffness. Twenty-two of the patients with mitral regurgitation underwent mitral valve surgery. In Group I, comparable decreases in left ventricular volume indexes (p < 0.01 and p = 0.05, respectively) were associated with no change in ejection fraction at 3 months and 1 year. In contrast, in Group II, reductions in volume indexes (p < 0.0001 and p < 0.001) were associated with a short-term decrease in ejection fraction (p < 0.001) that recovered at 1 year (p < 0.01 vs. short-term). Finally, in Group III, variable responses in volume indexes were associated with a consistent decrease in ejection fraction at 3 months and 1 year. CONCLUSIONS: An analysis of left ventricular chamber elastance provides data to support the concepts that 1) contractile function is impaired in some patients with long-term mitral regurgitation and a normal ejection fraction, 2) impaired contractile function may not be irreversible in all of these patients, and 3) an earlier consideration of mitral valve surgery may be warranted to preserve contractile function in these patients.
Assuntos
Insuficiência da Valva Mitral/fisiopatologia , Contração Miocárdica/fisiologia , Volume Sistólico , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Estudos de Casos e Controles , Cineangiografia , Feminino , Seguimentos , Imagem do Acúmulo Cardíaco de Comporta , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/cirurgiaRESUMO
Although percutaneous transluminal coronary angioplasty is successful in more than 90% of patients after acute coronary occlusion, overall mortality remains approximately 10% with higher subgroup mortality (i.e., occlusion of the left anterior descending coronary artery, multivessel disease, age older than 70 years, cardiogenic shock) and early recovery of regional wall motion is marginal. This multicenter report shows that controlled surgical reperfusion in patients with acute coronary occlusion reduces overall and subgroup mortality and restores substantial early contractility. In a survey from six institutions, 156 consecutive patients with acute coronary occlusion documented by angiography underwent surgical revascularization with controlled reperfusion using amino acid-enriched blood cardioplegic solution on total vented bypass. Ventricular wall motion was studied by echocardiography or multiple gated acquisition scan on postoperative days 5 to 7 and scored independently (0 = normal, 1 = mild hypokinesia, 2 = severe hypokinesia, 3 = akinesia, 4 = dyskinesia). Results are compared with results in 1203 patients with acute coronary occlusion treated by angioplasty in five reported medical series. Surgically treated patients were revascularized at longer ischemic intervals (6.3 versus 3.9 hours, p < 0.05) and had a greater incidence of left anterior descending occlusion (61% versus 43%, p < 0.05), multivessel disease (42% versus 22%, p < 0.05), and cardiogenic shock (41% versus 10%, p < 0.05), with 12 patients undergoing cardiopulmonary resuscitation en route to the operating room. Surgical results were superior in all categories, with overall mortality reduced from 8.7% after angioplasty to 3.9% after coronary bypass (p < 0.05). All surgical deaths occurred in patients with preoperative cardiogenic shock. Regional wall motion recovered significantly (score < 2) in 131 of 150 (87%) surgically treated patients with an average score of 0.9 +/- 0.8 (normal to mild hypokinesia) despite longer ischemic times.
Assuntos
Angioplastia Coronária com Balão , Ponte de Artéria Coronária , Doença das Coronárias/terapia , Doença Aguda , Sangue , Soluções Cardioplégicas , Doença das Coronárias/mortalidade , Parada Cardíaca Induzida/métodos , Humanos , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Estudos Retrospectivos , Choque Cardiogênico/mortalidadeRESUMO
Transfer factor, a dialyzable lymphocyte extract that may act as an immune stimulator by transferring antigen-specific immunity between genetically dissimilar individuals, was administered in a prospective, randomized study to patients with non-small cell bronchogenic carcinoma. Between 1976 and 1982, 63 patients who underwent pulmonary resection, mediastinal lymph node dissection, and, when indicated by the presence of mediastinal lymph node involvement, mediastinal irradiation were randomized into two groups. Group 1 (n = 28) received 1 mL of pooled transfer factor at 3-month intervals after operation; group 2 (n = 35 ) served as controls and received saline solution. There were no statistically significant differences between the two groups with respect to age, sex, tumor histology, stage of disease, or extent of resection. One patient was lost to follow-up at 96 months; follow-up was complete in all others through July 1990. In patients receiving transfer factor, the 2-, 5-, and 10-year survival rates were 82%, 64%, and 43% respectively, whereas in controls they were 63%, 43%, and 23%. Survival in patients receiving transfer factor was consistently better than in those receiving placebo. Furthermore, survival in patients receiving transfer factor was greater at all stages of disease for both adenocarcinoma and squamous cell carcinoma. Although these long-term results were not statistically significant using survival analysis with covariates (p = 0.08), they confirm our previously reported short-term findings suggesting that administration of transfer factor, either through nonspecific immune stimulation, enhancement of cell-mediated immunity, or an as yet undefined mechanism, can improve survival in patients with bronchogenic carcinoma.
Assuntos
Adjuvantes Imunológicos/uso terapêutico , Carcinoma Broncogênico/terapia , Neoplasias Pulmonares/terapia , Fator de Transferência/uso terapêutico , Adenocarcinoma/terapia , Carcinoma Broncogênico/mortalidade , Carcinoma Broncogênico/patologia , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Taxa de SobrevidaRESUMO
Seventy-four patients (16 women, 58 men, age 58 +/- 11 years, mean +/- standard deviation) who received an implantable cardioverter defibrillator (ICD) after experiencing a single episode of ventricular tachycardia or ventricular fibrillation were followed to determine if antiarrhythmic drug therapy affects the incidence of ICD discharges. Thirty-three patients (group A) were treated with an antiarrhythmic drug that was either untested or previously demonstrated during electropharmacological testing to be ineffective in suppressing the induction of ventricular tachycardia. Forty-one patients (group B) were not treated with an antiarrhythmic drug. There were no significant differences between the two groups in regards to age, sex, incidence of coronary artery disease, left ventricular function or the type of ICD pulse generator used. During a mean follow-up of 14 months for the entire cohort, 15 patients (46%) in group A and 18 patients (44%) in group B experienced at least one ICD shock. The time to the first appropriate shock (5 +/- 5 months in both groups) and the frequency of ICD shocks (0.3 +/- 0.2/month in group A vs 0.4 +/- 0.5/month in group B) were similar in both groups. The incidence of syncope at the time of ICD discharge was higher in group A than group B patients (31% vs 5%, P less than 0.05). In conclusion, antiarrhythmic drugs that are untested or have failed electropharmacological testing do not appear to reduce the probability of ICD discharge over a short-term (mean 14 months) follow-up in patients who have had only one clinical episode of VT/VF and may increase the risk of syncope during ICD discharge.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Antiarrítmicos/uso terapêutico , Cardioversão Elétrica/instrumentação , Próteses e Implantes , Taquicardia/terapia , Fibrilação Ventricular/terapia , Estimulação Cardíaca Artificial , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Síncope/epidemiologia , Taquicardia/epidemiologia , Fibrilação Ventricular/epidemiologiaRESUMO
A case is presented in which left subpleural hematoma and hemothorax resulted from a penetrating atherosclerotic aortic ulcer with an aortic pseudoaneurysm and intramedial hematoma. Percutaneous transfemoral embolization of the ulcer with use of coils and thrombin resulted in stabilization of the patient's hemodynamic status. The patient died 6 days later of pneumonia. In certain clinical situations, treatment of bleeding from penetrating aortic ulcers with percutaneous embolization may stabilize the patient's condition, allowing elective surgical intervention.
Assuntos
Aneurisma Aórtico/terapia , Dissecção Aórtica/terapia , Arteriosclerose/terapia , Embolização Terapêutica , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/complicações , Aorta Torácica/diagnóstico por imagem , Aneurisma Aórtico/complicações , Arteriosclerose/complicações , Hematoma/etiologia , Hemotórax/etiologia , Humanos , Masculino , Tomografia Computadorizada por Raios XRESUMO
Protamine reversal of heparin anticoagulation is associated with adverse hemodynamic effects that may be attenuated with protamine pretreatment (PP). This study assesses the role of complement activation during these phenomena in adult cardiac surgery patients. Sixteen individuals undergoing cardiopulmonary bypass were given intravenous normal saline or protamine (2 mg/kg) as a randomized pretreatment prior to undergoing heparin anticoagulation (400 IU/kg), coronary artery revascularization, and subsequent reversal of the anticoagulated state with protamine (4 mg/kg). Blood pressure, pulmonary artery diastolic pressure (PAD), heart rate, and cardiac output (CO) were measured during and after pretreatment, prior to heparin reversal by protamine, and for 10 min after reversal. Total hemolytic complement (CH50), C3 conversion to C3b, C3a/C5a, platelet count, and white blood cell count (WBC) were also measured at the same time periods. No significant correlation existed between complement activation and hemodynamic events, as might have been evident by decreased CH50, increased C3 conversion to C3b, or elevations in C3a/C5a levels. PP significantly prevented the CO decrease occurring at 1 and 3 min following heparin reversal by protamine (-0.8 and -1.4 liters/min vs 0.1 and -0.2 liters/min, P less than 0.05 and P less than 0.01, respectively). Reversal hypotension was less with PP, although PAD fell equally in both groups. WBC decreases after heparin reversal were less after PP (-25% vs -7%, P = 0.06). These data support the conclusion that, contrary to earlier reports, adverse hemodynamic and hematologic responses accompanying protamine reversal of heparin anticoagulation do not appear to be correlated with activation of complement. In fact, those patients having the greatest C3a generation exhibited the least hemodynamic changes.
Assuntos
Anticoagulantes/antagonistas & inibidores , Proteínas do Sistema Complemento/fisiologia , Antagonistas de Heparina/farmacologia , Protaminas/farmacologia , Adulto , Idoso , Débito Cardíaco/efeitos dos fármacos , Ponte Cardiopulmonar , Ativação do Complemento , Complemento C3/metabolismo , Complemento C3b/metabolismo , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The automatic internal cardioverter defibrillator (AICD) is effective in preventing death in patients with malignant ventricular arrhythmias (VT/VF) refractory to medical therapy. Because of the long waiting period for heart transplantation and the high likelihood of sudden arrhythmic death in this population, this study was undertaken to assess the value of the AICD in patients awaiting heart transplantation who have refractory VT/VF. Fourteen patients awaiting heart transplantation who had a history of VT/VF underwent AICD implantation (10 extrapericardial and four intrapericardial) via median sternotomy. All patients survived the AICD implantation and have either had heart transplantation or await transplantation at present (1 to 24 months after AICD implantation). Twelve of these patients have received a mean of 10 AICD shocks (range, 0 to 32). One patient received 19 shocks in the 24-hour period before transplantation. Two patients have died of progressive heart failure. Five patients have gone on to successful transplantation, and seven patients await heart transplantation with a functioning AICD in place. In conclusion, the AICD represents a new "bridge" to heart transplantation that is well tolerated by these high-risk patients, avoids drug side effects, and is efficacious in aborting sudden death, thereby allowing them to undergo successful heart transplantation.
Assuntos
Cardioversão Elétrica/instrumentação , Transplante de Coração , Próteses e Implantes , Análise Atuarial , Morte Súbita Cardíaca/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia/terapia , Fatores de Tempo , Fibrilação Ventricular/terapia , Listas de EsperaRESUMO
A 46-year-old man could not be weaned from ventilatory support while receiving procainamide. When the drug was discontinued, the patient was successfully weaned shortly thereafter.
Assuntos
Ponte Cardiopulmonar , Procainamida/efeitos adversos , Insuficiência Respiratória/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Desmame do RespiradorRESUMO
To test the hypothesis that the combined use of the time-varying elastance concept and conventional circumferential stress-shortening relations would elucidate differential mechanisms for left ventricular systolic dysfunction in severe, chronic aortic regurgitation and therefore predict the functional responses to aortic valve replacement, 31 control patients and 37 patients with aortic regurgitation were studied. The studies included micromanometer left ventricular pressure determinations, biplane contrast cineangiograms under control conditions and radionuclide angiograms under control conditions and during methoxamine or nitroprusside infusions with right atrial pacing. The patients with aortic regurgitation were classified into three groups: Group I had normal Emax and stress-shortening relations, Group II had abnormal Emax but normal stress-shortening relations and Group III had abnormal Emax and stress-shortening relations. The left ventricular end-diastolic and end-systolic volumes showed a progressive increase and the ejection fraction showed a progressive decrease from Group I to III; these values differed from those in the control patients (p less than 0.001). In Group I, there was a decrease in left ventricular volumes (p less than 0.05) but no significant change in ejection fraction (61 +/- 7% versus 63 +/- 4%) after aortic valve replacement. In contrast, in Group II, reduction in left ventricular volumes (p less than 0.01) was associated with an increase in ejection fraction from 50 +/- 8% to 64 +/- 11% (p less than 0.01). Finally, in Group III, reduction in left ventricular volumes (p less than 0.05) was associated with a further decrement in ejection fraction from 35 +/- 13% to 30 +/- 13%. Group I patients had compensated adequately for chronic volume overload. However, Group II had left ventricular dysfunction that was associated with an increase in the left ventricular volume/mass ratio compared with that in the control patients and Group I (p less than 0.05 for both), suggesting inadequate hypertrophy and assumption of spherical geometry. Finally, irreversible myocardial dysfunction had supervened in Group III. In conclusion, a combined analysis of left ventricular chamber performance using the time-varying elastance concept and myocardial performance using conventional circumferential stress-shortening relations provides complementary information that elucidates differential mechanisms for left ventricular systolic dysfunction and therefore predicts the functional response to aortic valve replacement.
Assuntos
Insuficiência da Valva Aórtica/fisiopatologia , Próteses Valvulares Cardíacas , Função Ventricular Esquerda/fisiologia , Valva Aórtica , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/cirurgia , Estimulação Cardíaca Artificial , Cineangiografia , Feminino , Imagem do Acúmulo Cardíaco de Comporta , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico/fisiologiaRESUMO
A 49-year-old man suffered multiple recurrences of pseudoaneurysm following ventricular aneurysmectomy in which Teflon felt strips had been used to reinforce the closure. The pseudoaneurysm was secondary to infection of the cardiac suture line, caused by a pathogen resident in the multifilamented Teflon strips. The patient was treated successfully by removal of all residual foreign material and reinforcement of the suture line with an omental pedicle graft.
RESUMO
A technique is described for bypassing the posterior lateral branch of the right coronary artery by passing the vein graft beneath the inferior vena cava to avoid kinking of the graft.