Low Back Pain During Streptokinase Infusion

We report the case of a 57-year-old male patient with severe low back pain during streptokinase infusion administered to treat typical chest pain and elevation of the ST segment in the inferior wall. We reviewed the literature, emphasizing the differential diagnosis, the pathophysiology, and management of the event.

Can patients with left main coronary artery disease wait for myocardial revascularization surgery?

OBJECTIVE: To assess the occurrence of cardiac events in patients diagnosed with left main coronary artery disease on diagnostic cardiac catheterization and waiting for myocardial revascularization surgery. METHODS: All patients diagnosed with left main coronary artery disease (stenosis > or = 50%) consecutively identified on diagnostic cardiac catheterization during an 8-month period were selected for the study. The group comprised 56 patients (40 males and 16 females) with a mean age of 61±10 years. The cardiac events included death, nonfatal acute myocardial infarction, acute left ventricular failure, unstable angina, and emergency surgery. RESULTS: While waiting for surgery, patients experienced the following cardiac events: 7 acute myocardial infarctions and 1 death. All events occurred within the first 60 days after the diagnostic cardiac catheterization. More patients, whose indication for diagnostic cardiac catheterization was unstable angina, experienced events as compared with those with other indications [p=0.03, relative risk (RR) = 5.25, 95% confidence interval = 1.47 - 18.7]. In the multivariate analysis of logistic regression, unstable angina was also the only factor that independently contributed to a greater number of events (p = 0.02, OR = 8.43, 95% CI =1.37 - 51.7). CONCLUSION: Unstable angina in patients with left main coronary artery disease acts as a high risk factor for cardiac events, emergency surgery being recommended in these cases.

Subendocardial fibrosis in remote myocardium results from reduction of coronary driving pressure during acute infarction in rats

OBJECTIVE: To investigate the role of hemodynamic changes occurring during acute MI in subsequent fibrosis deposition within non-MI. METHODS: By using the rat model of MI, 3 groups of 7 rats each [sham, SMI (MI <30%), and LMI (MI >30%)] were compared. Systemic and left ventricular (LV) hemodynamics were recorded 10 minutes before and after coronary artery ligature. Collagen volume fraction (CVF) was calculated in picrosirius red-stained heart tissue sections 4 weeks later. RESULTS: Before surgery, all hemodynamic variables were comparable among groups. After surgery, LV end-diastolic pressure increased and coronary driving pressure decreased significantly in the LMI compared with the sham group. LV dP/dt max and dP/dt min of both the SMI and LMI groups were statistically different from those of the sham group. CVF within non-MI interventricular septum and right ventricle did not differ between each MI group and the sham group. Otherwise, subendocardial (SE) CVF was statistically greater in the LMI group. SE CVF correlated negatively with post-MI systemic blood pressure and coronary driving pressure, and positively with post-MI LV dP/dt min. Stepwise regression analysis identified post-MI coronary driving pressure as an independent predictor of SE CVF. CONCLUSION: LV remodeling in rats with MI is characterized by predominant SE collagen deposition in non-MI and results from a reduction in myocardial perfusion pressure occurring early on in the setting of MI.

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.

Escore TIMI no infarto agudo do miocárdio conforme níveis de estratificação de prognóstico

FUNDAMENTO: O escore de risco TIMI (thrombolysis in myocardial infarction) é derivado de ensaio clínico envolvendo pacientes elegíveis para fibrinólise. Como o perfil de risco desses casos difere do encontrado em populações não selecionadas, é importante que se analise a aplicabilidade do escore em condições clínicas habituais. OBJETIVO: Avaliar o manejo e a evolução hospitalar de pacientes internados com infarto agudo do miocárdio conforme estratificação de risco pelo escore TIMI. MÉTODOS: Foram avaliados, retrospectivamente, 103 casos de infarto agudo do miocárdio com supradesnivelamento do segmento ST, admitidos no Hospital Nossa Senhora da Conceição, em Tubarão, nos anos de 2004 e 2005. Os casos foram analisados em três grupos de risco de acordo com o escore TIMI. RESULTADOS: A mortalidade hospitalar pós-infarto foi de 17,5%. No grupo de baixo risco não houve óbito. A mortalidade foi de 8,1% no grupo de médio risco e de 55,6% no de alto risco. O risco de morte para casos de alto risco foi 14,1 vezes maior em relação aos casos de médio e baixo risco (IC95% = 4,4 a 44,1 e p<0,001). A chance de receber fibrinolítico foi 50% menor no grupo de alto risco em relação ao de baixo risco (IC95%= 0,27 - 0,85; p=0,004). CONCLUSÃO: Houve um aumento progressivo na mortalidade e na ocorrência de complicações hospitalares conforme estratificação pelo escore TIMI. Pacientes de alto risco receberam trombolítico menos frequentemente que pacientes de baixo risco.

Níveis NT-Pro-BNP e resposta ao exercício em pacientes com fluxo lento coronariano

FUNDAMENTO: Os peptídeos natriuréticos são liberados pelo coração em resposta ao estresse da parede. OBJETIVO: As concentrações de NT-Pro-BNP em pacientes com Fluxo Lento Coronariano (FLC) foram avaliadas antes e depois do teste de exercício e comparados com os valores dos controles saudáveis. MÉTODOS: A população do estudo foi de 34 pacientes com FLC [22 homens (64,7%), com idade 51,0 ± 6,2 anos], e 34 indivíduos normais com artérias coronarianas normais [21 homens (61,8%), com idade 53,2 ± 6,6 anos]. As taxas de fluxo coronariano dos pacientes e controles foram determinadas pelo escore TIMI Trombólise no Infarto do Miocárdio (Thrombolysis in Myocardial Infarction). As amostras de sangue foram coletadas em repouso e após o teste ergométrico. RESULTADOS: As concentrações basais de NT-Pro-BNP nos pacientes com FLC foram superiores às dos indivíduos-controle (NT-Pro-BNP: 49,7 ± 14,2 pg/mL vs. 25,3 ± 4,6 pg/mL p <0,0001, respectivamente), e essa diferença entre os grupos aumentou após o teste de exercício (NT-Pro-BNP: 69,5 ± 18,6 pg/mL vs. 30,9 ± 6,4 pg/mL, p <0,0001). No grupo FLC após o exercício, a concentração de NT-Pro-BNP em 15 pacientes com angina foi maior do que aqueles sem angina (76,8 ± 17,8 pg/mL vs. 63,8 ± 17,5 pg/mL, p = 0,041).A concentração de NT-Pro-BNP em 11 pacientes com infradesnivelamento do segmento ST foi também maior do que aqueles sem infradesnivelamento do segmento ST (82,4 ± 17,3 pg/mL vs. 63,3 ± 16,1 pg/mL, p = 0,004). Os aumentos na mediana pós-exercício no NT-Pro-BNP (Δ NT-Pro-BNP) foram maiores no grupo FLC do que no grupo de controle (Δ NT-Pro-BNP: 19,8 ± 7,7 pg/mL vs. 5,7 ± 4,5 pg/mL, p < 0,0001). CONCLUSÃO: Os resultados deste estudo sugerem que pode haver uma ligação fisiopatológica importante entre a gravidade do FLC (microvascular ou disfunção da artéria coronária epicárdica) e o nível de circulação de NT-Pro-BNP em pacientes com FLC.

Myocardial Scintigraphy in the Evaluation of Cardiac Events in Patients without Typical Symptoms

AbstractBackground:Cardiovascular disease is a leading cause of death in the world and in Brazil. Myocardial scintigraphy is an important noninvasive method for detecting ischemia in symptomatic patients, but its use in asymptomatic ones or those with atypical symptoms is yet to be defined.Objective:To verify the presence of major cardiac events in asymptomatic patients or those with atypical symptoms (atypical chest pain or dyspnea) that underwent myocardial scintigraphy (MS), over a period of 8 years. Secondary objectives were to identify cardiac risk factors associated with myocardial scintigraphy abnormalities and possible predictors for major cardiac events in this group.Methods:This was a retrospective, observational study using the medical records of 892 patients that underwent myocardial scintigraphy between 2005 and 2011 and who were followed until 2013 for assessment of major cardiac events and risk factors associated with myocardial scintigraphy abnormalities. Statistical analysis was performed by Fisher’s exact test, logistic regression and Kaplan-Meyer survival curves, with statistical significance being set at p ≤ 0.05.Results:Of the total sample, 52.1% were men, 86.9% were hypertensive, 72.4% had hyperlipidemia, 33.6% were diabetic, and 12.2% were smokers; 44.5% had known coronary artery disease; and 70% had high Framingham score, 21.8% had moderate and 8% had low risk. Of the myocardial scintigraphies, 58.6% were normal, 26.1% suggestive of fibrosis and 15.3% suggestive of ischemia. At evolution, 13 patients (1.5%) had non-fatal myocardial infarction and six individuals (0.7%) died. The group with normal myocardial scintigraphy showed longer period of time free of major cardiac events, non-fatal myocardial infarction (p = 0.036) and death. Fibrosis in the myocardial scintigraphy determined a 2.4-fold increased risk of non-fatal myocardial infarction and five-fold higher risk of death (odds ratio: 2.4 and 5.7, respectively; p = 0.043).Conclusion:The occurrence of major cardiac events in 8 years was small. Patients with fibrosis at MS had more major events, whereas patients with normal MS result had fewer major cardiac events, with higher survival.

First- Versus Second-Generation Drug-Eluting Stents in Acute Coronary Syndromes (Katowice-Zabrze Registry)

Abstract Background: There are sparse data on the performance of different types of drug-eluting stents (DES) in acute and real-life setting. Objective: The aim of the study was to compare the safety and efficacy of first- versus second-generation DES in patients with acute coronary syndromes (ACS). Methods: This all-comer registry enrolled consecutive patients diagnosed with ACS and treated with percutaneous coronary intervention with the implantation of first- or second-generation DES in one-year follow-up. The primary efficacy endpoint was defined as major adverse cardiac and cerebrovascular event (MACCE), a composite of all-cause death, nonfatal myocardial infarction, target-vessel revascularization and stroke. The primary safety outcome was definite stent thrombosis (ST) at one year. Results: From the total of 1916 patients enrolled into the registry, 1328 patients were diagnosed with ACS. Of them, 426 were treated with first- and 902 with second-generation DES. There was no significant difference in the incidence of MACCE between two types of DES at one year. The rate of acute and subacute ST was higher in first- vs. second-generation DES (1.6% vs. 0.1%, p < 0.001, and 1.2% vs. 0.2%, p = 0.025, respectively), but there was no difference regarding late ST (0.7% vs. 0.2%, respectively, p = 0.18) and gastrointestinal bleeding (2.1% vs. 1.1%, p = 0.21). In Cox regression, first-generation DES was an independent predictor for cumulative ST (HR 3.29 [1.30-8.31], p = 0.01). Conclusions: In an all-comer registry of ACS, the one-year rate of MACCE was comparable in groups treated with first- and second-generation DES. The use of first-generation DES was associated with higher rates of acute and subacute ST and was an independent predictor of cumulative ST.

Increased angiotensin-converting enzyme activity in the left ventricle after infarction

An increase in angiotensin-converting enzyme (ACE) activity has been observed in the heart after myocardial infarction (MI). Since most studies have been conducted in chronically infarcted individuals exhibiting variable degrees of heart failure, the present study was designed to determine ACE activity in an earlier phase of MI, before heart failure development. MI was produced in 3-month old male Wistar rats by ligation of the anterior branches of the left coronary artery, control rats underwent sham surgery and the animals were studied 7 or 15 days later. Hemodynamic data obtained for the anesthetized animals showed normal values of arterial blood pressure and of end-diastolic pressure in the right and left ventricular cavities of MI rats. Right and left ventricular (RV, LV) muscle and scar tissue homogenates were prepared to determine ACE activity in vitro by measuring the velocity of His-Leu release from the synthetic substrate Hyp-His-Leu. ACE activity was corrected to the tissue wet weight and is reported as nmol His-Leu g-1 min-1. No significant change in ACE activity in the RV homogenates was demonstrable. A small nonsignificant increase of ACE activity (11 &plusmn; 9%; P0.05) was observed 7 days after MI in the surviving left ventricular muscle. Two weeks after surgery, however, ACE activity was 46 &plusmn; 11% (P<0.05) higher in infarcted rats compared to sham-operated rats. The highest ACE activity was demonstrable in the scar tissue homogenate. In rats studied two weeks after surgery, ACE activity in the LV muscle increased from 105 &plusmn; 7 nmol His-Leu g-1 min-1 in control hearts to 153 &plusmn; 11 nmol His-Leu g-1 min-1 (P<0.05) in the remaining LV muscle of MI rats and to 1051 &plusmn; 208 nmol His-Leu g-1 min-1 (P<0.001) in the fibrous scar. These data indicate that ACE activity increased in the heart after infarction before heart failure was demonstrable by hemodynamic measurements. Since the blood vessels of the scar drain to the remaining LV myocardium, the high ACE activity present in the fibrous scar may increase the angiotensin II concentration and decrease bradykinin in the cardiac tissues surrounding the infarcted area. The increased angiotensin II in the fibrous scar may contribute to the reactive fibrosis and hypertrophy in the left ventricular muscle surviving infarction

Evaluation of stunned and infarcted canine myocardium by real time myocardial contrast echocardiography

Differentiation between stunned and infarcted myocardium in the setting of acute ischemia is challenging. Real time myocardial contrast echocardiography allows the simultaneous assessment of myocardial perfusion and function. In the present study we evaluated infarcted and stunned myocardium in an experimental model using real time myocardial contrast echocardiography. Sixteen dogs underwent 180 min of coronary occlusion followed by reperfusion (infarct model) and seven other dogs were submitted to 20 min of coronary occlusion followed by reperfusion (stunned model). Wall motion abnormality and perfusional myocardial defect areas were measured by planimetry. Risk and infarct areas were determined by tissue staining. In the infarct model, the wall motion abnormality area during coronary occlusion (5.52 ± 1.14 cm²) was larger than the perfusional myocardial defect area (3.71 ± 1.45 cm²; P < 0.001). Reperfusion resulted in maintenance of wall motion abnormality (5.45 ± 1.41 cm²; P = 0.43 versus occlusion) and reduction of perfusional myocardial defect (1.51 ± 1.29 cm²; P = 0.004 versus occlusion). Infarct size determined by contrast echocardiography correlated with tissue staining (r = 0.71; P = 0.002). In the stunned model, the wall motion abnormality area was 5.49 ± 0.68 cm² during occlusion and remained 5.1 ± 0.63 cm² after reperfusion (P = 0.07). Perfusional defect area was 2.43 ± 0.79 cm² during occlusion and was reduced to 0.2 ± 0.53 cm² after reperfusion (P = 0.04). 2,3,5-Triphenyl tetrazolium chloride staining confirmed the absence of necrotic myocardium in all dogs in the stunned model. Real time myocardial contrast echocardiography is a noninvasive technique capable of distinguishing between stunned and infarcted myocardium after acute ischemia.

A comparative study of severe scorpion envenomation in children caused by Tityus bahiensis and Tityus serrulatus

From January 1984 to May 1994, 17 of 239 children under 15 years old stung by Tityus serrulatus (15.1%) or Tityus bahiensis (84.9%) presented severe envenoming. Of these 17 patients (1-11 years old; median=2 yr) 14 were stung by T.serrulatus and three by T.bahiensis. All of them received scorpion antivenom i.v. at times ranging from 45 min. to 5 h after the accident (median=2h). On admission, the main clinical manifestations and laboratory and electrocardiographic changes were: vomiting (17), diaphoresis (15), tachycardia (14), prostration (10), tachypnea (8), arterial hypertension (7), arterial hypotension (5), tremors (5), hypothermia (4), hyperglycemia (17), leukocytosis (16/16), hypokalemia (13/17), increased CK-MB enzyme activity (>6% of the total CK, 11/12), hyperamylasemia (11/14), sinusal tachycardia (16/17) and a myocardial infarction-like pattern (11/17). Six patients stung by T.serrulatus had depressed left ventricular systolic function assessed by means of echocardiography. Of these, five presented pulmonary edema and four had shock. A child aged two-years old presented severe respiratory failure and died 65 h after being stung by T.serrulatus. Severe envenomations caused by T.serrulatus were 26.2 times more frequent than those caused by T.bahiensis (p<0.001).

Protective effect of left ventricular hypertrophy in right coronary artery occlusions

OBJECTIVE: To test the hypothesis that left ventricular hypertrophy (LVH) reduces the electrocardiographic and functional effects of right coronary artery occlusion. METHODS: We analysed 215 patients (166 males and 49 women,age of 58.9±10.6 years), with occlusion of the right coronary artery without other associated lesions. There was no significant difference (p>0.05) in age and gender distribution between the 78 patients with LVH (left ventricular mass >100g/m²) (Group A) when compared with the 137 patients without LVH (left ventricular mass <100g/m²) (Group B). RESULTS: The electrocardiographic finding of transmural necrosis was more often found in group B patients than in group A patients (56.9% and 30.8%, respectively; p<0.05). The left ventricular function parameters of group A were better than those of group B: the ratio end-diastolic pressure/systolic pressure (EDP/SP) (A: 0.108±0.036; B: 0.121±0.050; p<0.05); the end-diastolic volume index (A: 75.9±31.3ml/m²; B: 88.0±31.0ml/m²; p<0.01); the end-systolic volume index (A: 16.0±10.0ml/m²; B: 27.0 ±20.0ml/m²; p<0.001); the ejection fraction (A 78.6±10.8%; B 67.7±17.9%; p<0.001); the anteroinferior shortening (A: 43.9±10.3%; B: 35.1±12.8%; p<0.001). A higher degree of coronary tortuosity was observed in group A than in group B (78.2% and 24.1%; p<0.001) and also a more frequent absent or minimal diaphragmatic hypokinetic area (A: 80.8%; B: 54.0%; p<0.05). CONCLUSION: LVH reduces the effects of myocardial sequela and protects LV function when right coronary occlusion develops.

Cholinergic stimulation with pyridostigmine, hemodynamic and echocardiographic analysis in healthy subjects

OBJECTIVE: Growing evidence suggests that sudden death after an acute myocardial infarction (AMI) correlates with autonomic nervous system imbalance. Parasympathomimetic drugs have been tested to reverse these changes. However, their effects on ventricular function need specific evaluation. Our objective was to analyze pyridostigmine's (PYR) effect on hemodynamic and echocardiographic variables of ventricular function. METHODS: Twenty healthy volunteers underwent Doppler echocardiographic evaluations, blood pressure (BP), and heart rate (HR) assessment at rest, before and 120 min after ingestion of 30 mg PYR or placebo, according to a double-blind, placebo-controlled, crossed and randomized protocol, on different days. RESULTS: PYR was well tolerated and did not cause alterations in BP or in ventricular systolic function. A reduction in HR of 10.9±1.3% occurred (p<0,00001). There was an A wave reduction in the mitral flow (p<0.01) and an E/A ratio increase (p<0.001) without changes in the other diastolic function parameters (p>0.05). CONCLUSION: PYR reduces HR and increases E/A ratio, without hemodynamic impairment or ventricular function change.

Coronary artery disease, microalbuminuria and lipid profile in patients with non-insulin dependent diabetes mellitus

PURPOSE: To determine the frequency of coronary artery disease, microalbuminuria and the relation to lipid profile disorders, blood pressure and clinical and metabolic features. METHODS: Fifty-five type 2 diabetic patients (32 females, 23 males), aged 59.9±9 years and with known diabetes duration of 11±7.3 years were studied. Coronary artery disease (CAD) was defined as a positive history of myocardial infarction, typical angina, myocardial revascularization or a positive stress testing. Microalbuminuria was defined when two out of three overnight urine samples had a urinary albumin excretion ranging 20 - 200µg/min. RESULTS: CAD was present in 24 patients (43,6%). High blood pressure (HBP) present in 32 patients (58.2%) and was more frequent in CAD group (p=0.05) HBP. Increased the risk of CAD 3.7 times (CI[1.14-12]). Microalbuminuria was present in 25 patients (45.5%) and tended to associate with higher systolic blood pressure (SBP) (p = 0.06), presence of hypertension (p = 0.06) and know diabetes duration (p = 0.08). In the stepwise multiple logistic regression the systolic blood pressure was the only variable that influenced UAE (r = 0.39, r² = 0.14, p = 0.01). The h ypertensive patients had higher cholesterol levels (p = 0.04). CONCLUSION: In our sample the frequency of microalbuminuria, hypertension, hypercholesterolemia and CHD was high. Since diabetes is an independent risk factor for cardiovascular disease, the association of others risk factors suggest the need for an intensive therapeutic intervention in primary and in secundary prevention.