Sleep-disordered breathing and chronic atrial fibrillation.

BACKGROUND: Little has been known about the prevalence of sleep apnea in patients with atrial fibrillation (AF). Studies have suggested that the prevalence of AF is increasing in patients with sleep-disordered breathing. We hypothesize that the prevalence of OSA is higher in chronic persistent and permanent AF patients than a sub-sample of the general population without this arrhythmic disorder. OBJECTIVE: Evaluate the frequency of Obstructive Sleep Apnea in a sample of chronic AF compared to a sub-sample of the general population. METHODS: Fifty-two chronic AF patients aged (60.5 +/- 9.5, 33 males) and 32 control (aged 57.3 +/- 9.6, 15 males). All subjects were evaluated by a staff cardiologist for the presence of medical conditions and were referred for polysomnography. The differences between groups were analyzed by ANOVA for continuous variables, and by the Chi-square test for dichotomous variables. Statistical significance was established by alpha=0.05. RESULTS: There were no differences in age, gender, BMI, sedentarism, presence of hypertension, type 2 diabetes mellitus, abdominal circumference, systolic and diastolic blood pressure, and sleepiness scoring between groups. Despite similar BMI, AF patients had a higher neck circumference compared to control group (39.9cm versus 37.7cm, p=0.01) and the AF group showed higher percentage time of stage 1 NREM sleep (6.4% versus 3.9%, p=0.03). Considering a cut-off value for AHI >= 10 per hour of sleep, the AF group had a higher frequency of OSA compared to the control group (81.6% versus 60%, p=0.03). All the oxygen saturation parameters were significantly worse in the AF group, which had lower SaO(2) nadir (81.9% versus 85.3%, p=0.01) and mean SaO(2) (93.4% versus 94.3%, p=0.02), and a longer period of time below 90% (26.4min versus 6.7min, p=0.05). CONCLUSION: Sleep-disordered breathing is more frequent in chronic persistent and permanent AF patients than in age-matched community dwelling subjects.

Tromboembolismo pulmonar: anticoagulação ou trombólise? / Pulmonary thromboembolism: anticoagulation or thrombolysis?

A terapia trombolítica é freqüentemente indicada nos pacientes com tromboembolismo pulmonar grave, principalmente naqueles que se apresentam com instabilidade hemodinâmica, hipoxemia grave e sinais de falência do ventrículo direito ao ecocardiograma. Nas últimas três décadas, vários estudos demonstraram a superioridade da terapia trombolítica, seja com a estreptoquinase, a uroquinase, ou a rt-PA, na restauração precoce da perfusão pulmonar. A rápida lise do trombo é acompanhada pela redução da hipertensão pulmonar e dos achados ecocardiográficos compatíveis com elevação da pós-carga do ventrículo direito. Entretanto, o impacto da terapia trombolítica em relação à heparina na sobrevida dos pacientes sem sinais de instabilidade hemodinâmica, especialmente na mortalidade hospitalar, recorrência e riscos de sangramento, não está esclarecido e tem sido motivo de recentes estudos multicêntricos. Os pacientes com sinais de instabilidade clínica também deverão ser considerados para tratamento trombolítico, respeitando-se as contra-indicaçöes de seu uso geral.

Arritmias e marcapasso em UTI / Arrhythmias and pacemaker in intensive care units

O objetivo deste artigo foi revisar as mais freqüentes arritmias cardíacas em pacientes internados em Unidades de Terapia Intensiva, assim como as indicaçöes e o manuseio do marcapasso temporário.

[Retroesophageal hematoma with severe dysfagia after streptokinase for the treatment of the axillosubclavian vein thrombosis]. / Hematoma retroesofágico com grave disfagia após estreptoquinase para tratamento da trombose venosa axilo-subclávia.

We report the case of a 72 year-old man with advanced, stage IV, prostate cancer who underwent osteosynthesis of the cervical spine for nerve root decompression due to metastasis which was causing severe pain in his right upper limb. After three months in the hospital, he developed occlusive thrombosis of the right axillosubclavian vein as a complication of prolonged catheterization of the right subclavian vein for treatment of septicemia secondary to a hospital acquired pneumonia. The patient received thrombolytic therapy with IV streptokinase in the contralateral arm in the following dosage: 250,000 units in 15 minutes followed by 100,000 units per hour during five days. This led to total recanalization of the thrombus, with significant reduction of the arm edema. Twenty-four hours after the end of the thrombolytic therapy, the patient started to complain of dysfagia to solids and liquids and a contrasted esophagogram revealed extensive extrinsic compression of the esophagus due to a probable retroesophageal hematoma. The patient required enteral nutrition via nasoenteral tube during three months after which swallowing returned to normal and a repeat upper GI series confirmed that the hematoma had been reabsorbed, with normal passage of contrast through the esophagus. On late follow-up, the patient did not show evidence of any sequelae of deep venous thrombosis nor any residual dysfagia and is currently in use of elastic stockings and low molecular weight heparin.

[Use of tissue plasminogen activator factor for acute ischemic stroke]. / Uso do fator ativador do plasminogênio tecidual no acidente vascular cerebral isquêmico agudo.

PURPOSE: To evaluate thrombolytic therapy with rt-PA for acute stroke within 6h of symptom onset, and assessment of neurologic outcome. METHODS: We studied 6 patients, four women, mean age 63 +/- 18 years, with severe neurologic deficit within 6h of stroke onset, and with no spontaneous improvement. The stroke was embolic in 3, and thrombotic in the others. All patients were submitted to a head CT scan followed by either a cerebral angiography in 3 patients, or a transcranial Doppler, in the other 3 for assessment of arterial obstruction, and patency after thrombolytic therapy. We used 0.9 mg/kg of rt-PA, IV, over 60 min in 5 patients, and 0.5 mg/kg by intra-arterial infusion, over 60 min, in one. At the beginning a bolus of 10% of the total dose was delivered during 1 to 2 min. Head scan was repeated 24h and 7 days after treatment to detect ischemic areas and hemorrhagic complications. RESULTS: Middle cerebral artery occlusion was observed in 5 patients and posterior cerebral artery occlusion in one. The obstruction was cleared in 4 patients with persistence of the patency after 24h. A complete neurologic recovery was found in one patient, and a partial recovery in three. In two patients there was failure of arterial recanalization with no neurologic recovery. Only one patient had hemorrhagic transformation of ischemic tissue, without neurologic worsening. Death occurred in one patient due to pulmonary infection. CONCLUSION: Arterial patency with thrombolytic therapy was effective in 4 of our 6 patients. All 4 patients also disclosed a certain degree of neurologic improvement, rt-PA can be successfully used in selected patients up to 3h of the event onset, as shown in randomized studies.

[Superior vena cava and right atrium thrombosis successfully treated with streptokinase]. / Trombose da veia cava superior e do átrio direito tratada com sucesso com estreptoquinase.

The case of a 56 year-old male with acute lymphoid leukemia and no signs of activity for the last four months is reported. He presented with superior vena cava thrombosis caused by a Hickman catheter, and had positive blood cultures for Candida albicans and Staphylococcus epidermidis. Despite adequate antimicrobial therapy, the fever persisted, and the patient was submitted to surgical thrombectomy. One week following the procedure, the fever returned, and thrombosis of the superior vena cava extending to the right atrium was identified by transesophageal echocardiography (TEE). The patient underwent thrombolytic therapy with streptokinase, and no thrombus could be identified in the control TEE. No hemorrhagic or thromboembolic complication occurred. The patient was discharged with oral anticoagulation.

[Hemodynamic impact of thrombolytic therapy in acute pulmonary thromboembolism]. / Repercussões hemodinâmicas da terapia trombolítica no tromboembolismo pulmonar agudo.

PURPOSE: To evaluate pre and post-hemodynamic changes after thrombolytic therapy in patients with acute pulmonary embolism with multiple pulmonary segments compromised. METHODS: Nine patients, 5 females, aged between 27 and 83 (mean 62 +/- 16) years, with the onset of symptoms preceding 7 days, were submitted to thrombolytic therapy, administered after baseline perfusion-ventilation lung scan, echodopplercardiography (ECO) and hemodynamic measurements with a Swan-Ganz thermodilution catheter. The same procedures were done after the thrombolytic infusion. Streptokinase (SK) was used in 7 (78%) cases and recombinant human tissue-type plasminogen activator (rt-PA, alteplase) in 2 with the following doses: SK-250,000 i.u. infusion over 30 min, then 100,000 i.v/h over 24 to 72 h and rt-PA-20 mg in bolus infusion, then 80 mg over 6 h. Thrombolytic was infused in pulmonary artery trunk in 8 (88%) cases and a peripheral vein in 1 (12%) case, until mean pulmonary artery pressure (PAP) reached 20 mmHg. All patients received i.v. heparin and oral anticoagulation after thrombolytic therapy. RESULTS: A significant (p < 0.05) decrease in right atrial pressure (12 +/- 3 vs 8 +/- 2 mmHg), PAP (32 +/- 5 vs 19 +/- 2 mmHg), pulmonary vascular resistance (397 +/- 125 vs 87 +/- 24 dyne.s/cm5) and increase in cardiac output (3.4 +/- 0.5 vs 5.5 +/- 1.0 l/min) and stroke volume (30 +/- 5 vs 57 +/- 10 ml/beat) were observed after thrombolytic infusion. Two patients died as a result of pulmonary infection unrelated to the embolic event or thrombolysis. Minor bleeding complications occurred in two cases and major in one patient with orthopedic prosthesis. CONCLUSION: Thrombolytic therapy exert desirable effects on hemodynamic abnormalities, achieving lungs scan and ECO improvement in patients with acute pulmonary embolism.

[Diagnosis of papillary muscle rupture in acute myocardial infarction by transesophageal Doppler echocardiography]. / Diagnóstico da rotura do músculo papilar no infarto agudo do miocárdio através do ecodopplercardiograma transesofágico.

Three patients, two females, ages ranging from 62 to 78 years were studied, evolving with hypotension, acute pulmonary edema and cardiogenic shock. One had anterior myocardial infarction, and in two, infero-posterior. Due to severe hemodynamic instability and necessity of vasoactive drug therapy to maintain adequate arterial pressure, coronary angiography was performed in two, showing total occlusion of the circumflex artery and severe mitral regurgitation. In one case, angioplasty on the circumflex artery was successfully achieved. No hemodynamic improvement was observed, however. Doppler echocardiography depicted mild to moderate mitral regurgitation in the three cases. Transesophageal echo confirmed the clinical suspicion of papillary muscle rupture: total rupture of antero-lateral papillary muscle in one patient, as well as total and partial rupture of the postero-medial papillary muscle in the other two patients. Two patients were submitted to mitral valve replacement, and the surgical findings confirmed the transesophageal echo conclusions. One of them died in the immediate pos-operative period, whereas the other was discharged from the hospital and is doing well. The third patient died before operation. Differential diagnosis of acute mitral regurgitation due to papillary muscle dysfunction or rupture was not possible by left ventriculography or by transthoracic echo. Transesophageal echo was the only exam to clearly confirm papillary muscle rupture, as should be done promptly after clinical suspicion of this severe condition arises.

[Post infarction ventricular septal defect. Echocardiographic analysis of patients treated with positive end-expiratory pressure]. / Comunicação interventricular após infarto do miocárdio. Análise ecocardiografica de pacientes submetidos a pressão expiratória final positiva.

Interventricular septal rupture is a life-threatening complication occurring in 0.5 to 1.0% of patients following acute myocardial infarction and often results in right and left ventricular failure. This study aimed at evaluating the echocardiographic effects of PEEP on right (RV) and left (LV) ventricular dimension in three patients who developed a postinfarction septal defect and in whom acute respiratory failure was a preterminal event. The effects of PEPP on the heart remain controversial. We observed in all three patients a sudden large increase in RV dimensions and hence, probably through ventricular interdependence, a proportional decrease in LV dimensions. The progressive leftward septal displacement with increasing levels of PEEP probably contributed to reduce LV compliance. We concluded that PEEP therapy in this group of patients had no proven beneficial effects and probably contributed to further RV dilatation and failure.

[Family with predominance of cardiac involvement in Steinert's disease]. / Família com predominância do comprometimento cardíaco na doença de Steinert.

We report an affected family (mother and two children) with prominent cardiac form as reflected by the mother, 49, with neuromuscular signs (muscular atrophy os face, neck and distally in the extremities) who received an implantable pacemaker after 2 consecutive episodes of syncope and baseline EKG with P-R of 250 ms, QRS of 130 ms (LBBB) and conduction system intervals displaying overt widening (AH of 140 ms with a ERP of junction tissue of 590 ms, and Wenckebach point of 115 bpm; and HV of 80 ms before and 95 ms after pharmacological stress with procainamide). As long as its mode of inheritance is autosomal dominant, the cardiovascular examination of her two affected siblings (F1 and F2) revealed: F1 (male, 31), with P-R of 180 ms and QRS of 100 ms; F2 (female, 27), with P-R of 200 ms and QRS of 100 ms, both with left axis deviation. Echocardiographic studies were normal in both, but Holter studies showed remarkable bradycardia in both and intermittent rate-related (phase 3) LBBB in F2. Also for F1 and F2 conduction system intervals, except for AH (normal in both), displayed severe widening (HV of 70 ms in F1 and of 80 ms in F2, but only in this later with a procainamide stress extra widening to 130 ms). All three patients showed normal NS function, as usual for the disease. F2 is kept under close surveillance for the appearance of any symptom. In conclusion, although rarely symptomatic, the intensity of IV conduction system damage should not be disregarded in this condition.

Taquicardia atrial e funçäo renal / Atrial tachycardia and renal function

A taquicardia atrial induzida artificialmente em cäo produziu nas nossas condiçöes, alteraçäo importante da funçäo renal. Essa alteraçäo se manifestou por significativo aumento do volume urinário por minuto (1,3 ñ 0,12 no controle para 3,2 ñ 0,6ml/min no experimental) e da fraçäo de excreçäo de sódio (FENa) (de 2,3 ñ 0,3 no controle para 3,6 ñ 0,5), na presença de queda significante do fluxo sanguíneo renal (317 ñ 30,9 para 232 ñ 26,7 ml/min), sem alterar o ritmo de filtraçäo glomerular (66,1 ñ 6,7 no controle para 70,6 ñ 6,5 ml/min no experimental). Quanto à hemodinâmica sistêmica, observamos queda signficante do débito cardíaco e aumentos significantes da resistência vascular sistêmica e da pressäo de capilar pulmonar. Esses resultados demonstram que possivelmente fatores näo relacionados à hemodinâmica sistêmica, mas relacionados a alteraçöes hormonais, sejam responsáveis por estas alteraçöes

Angiographic and electrophysiologic substrates of ventricular tachycardia in chronic Chagasic myocarditis.

Forty-three consecutive symptomatic patients with chronic Chagasic myocarditis and ventricular tachycardia (VT) underwent clinical evaluation, 24-hour Holter monitoring, left ventricular angiography and electrophysiologic testing including programmed ventricular stimulation at 3 drive cycle lengths at 2 sites in the right ventricle. The mean ejection fraction was 42 +/- 10%. Sixteen patients had clinical sustained VT and 27 nonsustained VT. VT was reproducibly initiated in 13 of 16 (81%) patients with sustained VT and in 14 of 27 (52%) patients with nonsustained VT. Electrocardiographic conduction disturbances were seen in 15 of 16 (94%) patients with sustained VT and in 17 of 27 (63%) patients with nonsustained VT (p less than 0.05). Five of 16 (31%) sustained VT and none of nonsustained VT patients had left ventricular aneurysms (p less than 0.05). These data indicate that VT is frequently inducible in patients with sustained VT and nonsustained VT and chronic Chagasic myocarditis. An association appears to be present between conduction disturbances on the electrocardiogram, left ventricular aneurysms and development of sustained ventricular arrhythmias.