Bundle branch and atrioventricular block as complications of acute myocardial infarction in the thrombolytic era

OBJECTIVE: To analyze the incidence of intraventricular and atrioventricular conduction defects associated with acute myocardial infarction and the degree of in hospital mortality resulting from this condition during the era of thrombolytic therapy. METHODS: Observational study of a cohort of 929 consecutive patients with acute myocardial infarction. Multivariate analysis by logistic regression. Was used. RESULTS: Logistic regression showed a greater incidence of bundle branch block in male sex (odds ratio = 1.87, 95% CI = 1.02-3.42), age over 70 years (odds ratio = 2.31, 95% CI = 1.68-5.00), anterior localization of the infarction (odds ratio = 1.93, 95% CI = 1.03-3.65). There was a greater incidence of complete atrioventricular block in inferior infarcts (odds ratio = 2.59, 95% CI 1.30-5.18) and the presence of cardiogenic shock (odds ratio = 3.90, 95% CI = 1.43-10.65). Use of a thrombolytic agent was associated with a tendency toward a lower occurrence of bundle branch block (odds ratio = 0.68) and a greater occurrence of complete atrioventricular block (odds ratio = 1.44). The presence of bundle branch block (odds ratio = 2.45 95% , CI = 1.14-5.28) and of complete atrioventricular block (odds ratio = 13.59, 95% CI = 5.43-33.98) was associated with a high and independent probability of inhospital death. CONCLUSION: During the current era of thrombolytic therapy and in this population, intraventricular disturbances of electrical conduction and complete atrioventricular block were associated with a high and independent risk of inhospital death during acute myocardial infarction.

Clinical impact of transesophageal echocardiography in patients with stroke without clinical evidence of cardiovascular sources of emboli

OBJECTIVE: The purpose of this study is to evaluate the impact of transeophageal echocardiography on management of patients at low-risk for cardiogenic embolism to prevent new potential cardiovascular sources of emboli. METHODS: We studied 69 patients with ischemic stroke at low-risk for cardiogenic embolism. Transeophageal echocardiography was performed to access: left atrium enlargement; communication or aneurysm of the interatrial septum; patent foramen ovale; spontaneous echo contrast or intracavitary thrombi; the presence of intraaortic atherosclerotic plaques or thrombi; significant valvar morphologic alteration or dysfunction; left ventricle enlargement, hypertrophy, or contractile abnormality. Transesophageal echocardiography altered clinical management, and we adopted anticoagulant therapy or another procedure apart from the use of acetylsalicylic acid. RESULTS: Transeophageal echocardiography detected at least one abnormality in 40 cases (58%). Clinical conduct was adjusted after the performance of transesophageal echocardiography in 11 patients (15.9%); anticoagulation was added in 10 cases and surgical correction in one patient. CONCLUSION: Transeophageal echocardiography was a very useful tool in the secondary prevention for stroke in patients at low risk for cardiogenic embolism.

Clinical Profile, Predictors of Mortality, and Treatment of Patients after Myocardial Infarction, in an Academic Medical Center Hospital

OBJECTIVE: To evaluate clinical profiles, predictors of 30-day mortality, and the adherence to international recommendations for the treatment of myocardial infarction in an academic medical center hospital. METHODS: We retrospectively studied 172 patients with acute myocardial infarction, admitted in the intensive care unit from January 1992 to December 1997. RESULTS: Most patients were male (68%), white (97%), and over 60 years old (59%). The main risk factor for coronary atherosclerotic disease was systemic blood hypertension (63%). Among all the variables studied, reperfusion therapy, smoking, hypertension, cardiogenic shock, and age were the predictors of 30-day mortality. Most commonly used medications were: acetylsalicylic acid (71%), nitrates (61%), diuretics (51%), angiotensin-converting enzyme inhibitors (46%), thrombolytic therapy (39%), and beta-blockers (35%). CONCLUSION: The absence of reperfusion therapy, smoking status, hypertension, cardiogenic shock, and advanced age are predictors of 30-day mortality in patients with acute myocardial infarction. In addition, some medications that are undoubtedly beneficial have been under-used after acute myocardial infarction.

Neonate Aortic Stenosis: Importance of Myocardial Perfusion in Prognosis

OBJECTIVE: To analyze our experience with percutaneous aortic balloon valvuloplasty in newborn infants with aortic stenosis, emphasizing the extraordinary importance of myocardial perfusion.METHODS: Over a 10-year-period, 21 neonates underwent percutaneous aortic balloon valvuloplasty. Age ranged from 2 to 27 days, weight ranged from 2.2 to 4.1 kg and 19 were males. All patients presented with congestive heart failure that could not be treated clinically. The onset of symptoms in the first week of life occurred in 9 patients considered as having critical aortic stenosis. Severe aortic stenosis occurred in 12 patients with the onset of symptoms in the second week of life.RESULTS: Mortality reached 100% in the patients with critical aortic stenosis. The procedure was considered effective in the 12 patients with severe aortic stenosis. Vascular complications included the loss of pulse in 12 patients and rupture of the femoral artery in 2 patients. Cardiac complications included acute aortic regurgitation in 2 patients and myocardial perforation in one. In an 8.2±1.3-year follow-up, 5 of the 12 patients died (2 patients due to septicemia and 3 patients due to congestive heart failure). Five of the other 7 patients underwent a new procedure and 2 required surgery.CONCLUSION: Percutaneous aortic valvuloplasty in neonates is not an effective procedure in the 1st week of life, because at this age the common presentation is cardiogenic shock. It is possible that, in those patients with critical aortic stenosis, dilation of the aortic valve during fetal life may change the prognosis of its clinical outcome.

Predictive factors of in-hospital mortality and of severe perioperative complications in myocardial revascularization surgery

OBJECTIVE: To investigate preoperative predictive factors of severe perioperative intercurrent events and in-hospital mortality in coronary artery bypass graft (CABG) surgery and to develop specific models of risk prediction for these events, mainly those that can undergo changes in the preoperative period. METHODS: We prospectively studied 453 patients who had undergone CABG. Factors independently associated with the events of interest were determined with multiple logistic regression and Cox proportional hazards regression model. RESULTS: The mortality rate was 11.3% (51/453), and 21.2% of the patients had 1 or more perioperative intercurrent events. In the final model, the following variables remained associated with the risk of intercurrent events: age ³ 70 years, female sex, hospitalization via SUS (Sistema Único de Saúde - the Brazilian public health system), cardiogenic shock, ischemia, and dependence on dialysis. Using multiple logistic regression for in-hospital mortality, the following variables participated in the model of risk prediction: age ³ 70 years, female sex, hospitalization via SUS, diabetes, renal dysfunction, and cardiogenic shock. According to the Cox regression model for death within the 7 days following surgery, the following variables remained associated with mortality: age ³ 70 years, female sex, cardiogenic shock, and hospitalization via SUS. CONCLUSION: The aspects linked to the structure of the Brazilian health system, such as factors of great impact on the results obtained, indicate that the events investigated also depend on factors that do not relate to the patient's intrinsic condition.

Aspergillus infection in the ascending aorta of a patient with aortic and mitral valve prostheses

We report the case of implantation of metallic mitral and aortic valve prostheses 6 months earlier, with subsequent multiple embolic episodes. The anatomicopathological examination of the thrombus of the third embolic episode was compatible with Aspergillus sp, which was treated with amphotericin B, followed by oral itraconazole. On the fourth embolism, vegetations were visualized in the ascending aorta on echocardiography and resonance imaging, and the patient underwent replacement of the aortic segment by a Haemashield tube and exploration of the aortic prosthesis, which was preserved, because no signs of endocarditis were found. Four months later, the patient died due to cardiogenic shock secondary to acute myocardial infarction caused by probable coronary embolism and partial dysfunction of the aortic prosthesis.

Impact of Different Obesity Assessment Methods after Acute Coronary Syndromes

Background: Abdominal obesity is an important cardiovascular risk factor. Therefore, identifying the best method for measuring waist circumference (WC) is a priority. Objective: To evaluate the eight methods of measuring WC in patients with acute coronary syndrome (ACS) as a predictor of cardiovascular complications during hospitalization. Methods: Prospective study of patients with ACS. The measurement of WC was performed by eight known methods: midpoint between the last rib and the iliac crest (1), point of minimum circumference (2); immediately above the iliac crest (3), umbilicus (4), one inch above the umbilicus (5), one centimeter above the umbilicus (6), smallest rib and (7) the point of greatest circumference around the waist (8). Complications included: angina, arrhythmia, heart failure, cardiogenic shock, hypotension, pericarditis and death. Logistic regression tests were used for predictive factors. Results: A total of 55 patients were evaluated. During the hospitalization period, which corresponded on average to seven days, 37 (67%) patients had complications, with the exception of death, which was not observed in any of the cases. Of these complications, the only one that was associated with WC was angina, and with every cm of WC increase, the risk for angina increased from 7.5 to 9.9%, depending on the measurement site. It is noteworthy the fact that there was no difference between the different methods of measuring WC as a predictor of angina. Conclusion: The eight methods of measuring WC are also predictors of recurrent angina after acute coronary syndromes.

Aortic Counterpulsation Therapy in Patients with Advanced Heart Failure: Analysis of the TBRIDGE Registry

Abstract Background: The use of aortic counterpulsation therapy in advanced heart failure is controversial. Objectives: To evaluate the hemodynamic and metabolic effects of intra-aortic balloon pump (IABP) and its impact on 30-day mortality in patients with heart failure. Methods: Historical prospective, unicentric study to evaluate all patients treated with IABP betwen August/2008 and July/2013, included in an institutional registry named TBRIDGE (The Brazilian Registry of Intra-aortic balloon pump in Decompensated heart failure - Global Evaluation). We analyzed changes in oxygen central venous saturation (ScvO2), arterial lactate, and use of vasoactive drugs at 48 hours after IABP insertion. The 30-day mortality was estimated by the Kaplan-Meier method and diferences in subgroups were evaluated by the Log-rank test. Results: A total of 223 patients (mean age 49 ± 14 years) were included. Mean left ventricle ejection fraction was 24 ± 10%, and 30% of patients had Chagas disease. Compared with pre-IABP insertion, we observed an increase in ScvO2 (50.5% vs. 65.5%, p < 0.001) and use of nitroprusside (33.6% vs. 47.5%, p < 0.001), and a decrease in lactate levels (31.4 vs. 16.7 mg/dL, p < 0.001) and use of vasopressors (36.3% vs. 25.6%, p = 0.003) after IABP insertion. Thirty-day survival was 69%, with lower mortality in Chagas disease patients compared without the disease (p = 0.008). Conclusion: After 48 hours of use, IABP promoted changes in the use of vasoactive drugs, improved tissue perfusion. Chagas etiology was associated with lower 30-day mortality. Aortic counterpulsation therapy is an effective method of circulatory support for patients waiting for heart transplantation.

Control of the adaptive response of the heart to stress via the Notch1 receptor pathway.

In the damaged heart, cardiac adaptation relies primarily on cardiomyocyte hypertrophy. The recent discovery of cardiac stem cells in the postnatal heart, however, suggests that these cells could participate in the response to stress via their capacity to regenerate cardiac tissues. Using models of cardiac hypertrophy and failure, we demonstrate that components of the Notch pathway are up-regulated in the hypertrophic heart. The Notch pathway is an evolutionarily conserved cell-to-cell communication system, which is crucial in many developmental processes. Notch also plays key roles in the regenerative capacity of self-renewing organs. In the heart, Notch1 signaling takes place in cardiomyocytes and in mesenchymal cardiac precursors and is activated secondary to stimulated Jagged1 expression on the surface of cardiomyocytes. Using mice lacking Notch1 expression specifically in the heart, we show that the Notch1 pathway controls pathophysiological cardiac remodeling. In the absence of Notch1, cardiac hypertrophy is exacerbated, fibrosis develops, function is altered, and the mortality rate increases. Therefore, in cardiomyocytes, Notch controls maturation, limits the extent of the hypertrophic response, and may thereby contribute to cell survival. In cardiac precursors, Notch prevents cardiogenic differentiation, favors proliferation, and may facilitate the expansion of a transient amplifying cell compartment.

Clinical use of temporary percutaneous left ventricular assist devices.

Background: Temporary percutaneous left ventricular assist devices (TPLVAD) can be inserted and removed in awake patients. They substitute left ventricular function for a period of up to a few weeks and provide an excellent backup and bridge to recovery or decision. Methods: Retrospective analysis of 75 patients who received TPLVAD to treat cardiogenic shock (n = 49) or to facilitate high-risk percutaneous coronary intervention (PCI) (n = 26). Forty-two patients with cardiogenic shock and 16 patients with high-risk PCI received a TandemHeart and 7 patients and 10 patients, respectively, received an Impella Recover LP 2.5. Outcome and related complications up to 1 month are reported with reference to device depending function. Results: One-month survival was 53% in patients with shock and 96% in patients with PCI. Conclusion: TPLVADs can support the failing heart with acceptable risk. Outcome is better in prophylactic use than in patients with cardiogenic shock. (C) 2011 Wiley-Liss, Inc.

Fatal myocardial infarction after lung resection in a patient with prophylactic preoperative coronary stenting.

In this report we present the case of a 77-yr-old man who underwent resection of the upper lobe of the left lung for a carcinoma, six weeks after percutaneous transluminal coronary angioplasty (PTCA) with stenting of the left anterior descending (LAD) and circumflex coronary arteries. Antiplatelet therapy with clopidogrel was interrupted two weeks before surgery to allow for epidural catheter placement and to minimize haemorrhage. The surgical procedure was uneventful. In the immediate postoperative period, however, the patient suffered severe myocardial ischaemia. Emergency coronary angiography showed complete thrombotic occlusion of the LAD stent. In spite of successful recanalization, reinfarction occurred and the patient died in cardiogenic shock. Prophylactic preoperative coronary stenting may put the patient at risk of stent thrombosis if surgery cannot be postponed for three months. In such cases, other strategies such as perioperative beta-blockade for preoperative cardiac management should be considered.

Cardiopulmonary support and extracorporeal membrane oxygenation for cardiac assist.

BACKGROUND: Use of cardiopulmonary bypass for emergency resuscitation is not new. In fact, John Gibbon proposed this concept for the treatment of severe pulmonary embolism in 1937. Significant progress has been made since, and two main concepts for cardiac assist based on cardiopulmonary bypass have emerged: cardiopulmonary support (CPS) and extracorporeal membrane oxygenation (ECMO). The objective of this review is to summarize the state of the art in these two technologies. METHODS: Configuration of CPS is now fairly standard. A mobile cart with relatively large wheels allowing for easy transportation carries a centrifugal pump, a back-up battery with a charger, an oxygen cylinder, and a small heating system. Percutaneous cannulation, pump-driven venous return, rapid availability, and transportability are the main characteristics of a CPS system. Cardiocirculatory arrest is a major predictor of mortality despite the use of CPS. In contrast, CPS appears to be a powerful tool for patients in cardiogenic shock before cardiocirculatory arrest, requiring some type of therapeutic procedures, especially repair of anatomically correctable problems or bridging to other mechanical circulatory support systems such as ventricular assist devices. CPS is in general not suitable for long-term applications because of the small-bore cannulas, resulting in significant pressure gradients and eventually hemolysis. RESULTS: In contrast, ECMO can be designed for longer-term circulatory support. This requires large-bore cannulas and specifically designed oxygenators. The latter are either plasma leakage resistent (true membranes) or relatively thrombo-resistant (heparin coated). Both technologies require oxygenator changeovers although the main reason for this is different (clotting for the former, plasma leakage for the latter). Likewise, the tubing within a roller pump has to be displaced and centrifugal pump heads have to be replaced over time. ECMO is certainly the first choice for a circulatory support system in the neonatal and pediatric age groups, where the other assist systems are too bulky. ECMO is also indicated for patients improving on CPS. Septic conditions are, in general, considered as contraindications for ECMO. CONCLUSIONS: Ease of availability and moderate cost of cardiopulmonary bypass-based cardiac support technologies have to be balanced against the significant immobilization of human resources, which is required to make them successful.

Therapy of acute massive pulmonary embolism associated with Klippel-Trenaunay syndrome.

Acute massive pulmonary embolism (PE) is a life-threatening event. Before the era of cardiopulmonary bypass, acute pulmonary embolectomy had been historically attempted in patients with severe hemodynamic compromise. The Klippel-Trenaunay syndrome (KTS) represents a significant life-long risk for major thromboembolic events. We present two young patients with Klippel-Trenaunay syndrome who survived surgical embolectomy after massive PE and cardiopulmonary resuscitation, with good postoperative recovery. Even though the role of surgical embolectomy in massive PE is not clearly defined, with current technology it can be life saving and can lead to a complete recovery, especially in young patients as described in this study.