RESUMO
Aims: Closed-loop stimulation (CLS) seemed promising in preventing the recurrence of vasovagal syncope (VVS) in patients with a cardioinhibitory response to head-up tilt test (HUTT) compared with conventional pacing. We hypothesized that the better results of this algorithm are due to its quick reaction in high-rate pacing delivered in the early phase of vasovagal reflex, which increase the cardiac output and the blood pressure preventing loss of consciousness. Methods and results: This prospective, randomized, single-blind, multicentre study was designed as an intra-patient comparison and enrolled 30 patients (age 62.2 ± 13.5 years, males 60.0%) with cardioinhibitory VVS, carrying a dual-chamber pacemaker incorporating CLS algorithm. Two HUTTs were performed one week apart: one during DDD-CLS 60-130/min pacing and the other during DDD 60/min pacing; patients were randomly and blindly assigned to two groups: in one the first HUTT was performed in DDD-CLS (n = 15), in the other in DDD (n = 15). Occurrence of syncope and haemodynamic variations induced by HUTT was recorded during the tests. Compared with DDD, DDD-CLS significantly reduced the occurrence of syncope induced by HUTT (30.0% vs. 76.7%; P < 0.001). In the patients who had syncope in both DDD and DDD-CLS mode, DDD-CLS significantly delayed the onset of syncope during HUTT (from 20.8 ± 3.9 to 24.8 ± 0.9 min; P = 0.032). The maximum fall in systolic blood pressure recorded during HUTT was significantly lower in DDD-CLS compared with DDD (43.2 ± 30.3 vs. 65.1 ± 25.8 mmHg; P = 0.004). Conclusion: In patients with cardioinhibitory VVS, CLS reduces the occurrence of syncope induced by HUTT, compared with DDD pacing. When CLS is not able to abort the vasovagal reflex, it seems to delay the onset of syncope.
Assuntos
Estimulação Cardíaca Artificial/métodos , Hemodinâmica , Prevenção Secundária/métodos , Síncope Vasovagal , Teste da Mesa Inclinada/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Recidiva , Índice de Gravidade de Doença , Método Simples-Cego , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/etiologia , Síncope Vasovagal/fisiopatologia , Tempo para o TratamentoRESUMO
Takotsubo cardiomyopathy (CT) is a syndrome characterized by an acute and transient left ventricular dysfunction, electrocardiographic abnormalities suggestive of acute coronary syndrome, chest pain and/or dyspnea, left ventricular mid-apical segments akinesia and normal coronary angiography. It is mainly observed in postmenopausal women after an intense physical or mental stress. The course is usually favourable but sometimes severe complications occur. The recurrence rate is 2-10%. We present the case of a recurrence of CT in a female, 79 years old, with hypertension, diabetes, chronic kidney disease (CKD) stage 3 who was admitted to the emergency room for dyspnea and vomiting. The electrocardiogram (ECG) showed a sinusal rhythm and T wave inversion in the pre-cordial leads and the echocardiogram a typical feature of CT with depressed left ventricular systolic function (FE). The ECG ranged quickly with atrial fibrillation rhythm, followed by a major hypokinetic arrhythmia with advanced atrio-ventricular block which indicated the need for a temporary pacemaker placement. The patient was oligouric, with severe renal failure, hyponatremia, hyperkalemia and metabolic acidosis. A continuous renal replacement therapy (CRRT) was started. On the seventh day improvement in urine output, electrolyte and acid base imbalance and FE normalization occurred. The renal function improved gradually, but after 36 months, persisted CKD stage 4. The case report describes the development of a cardiorenal syndrome type 1 induced by CT recurrence and effectiveness of CRRT in the management of acute heart failure. It also suggests a potential role played by CKD as a risk factor in the onset and recurrence of CT.
Assuntos
Insuficiência Renal Crônica/complicações , Cardiomiopatia de Takotsubo/etiologia , Idoso , Feminino , Humanos , RecidivaRESUMO
Coronary artery disease is the most common cause of heart failure in the western world. Due to shortage of donors, heart transplantation is not a realistic treatment for the great majority of patients with heart failure, while surgical revascularization is a valuable alternative in selected patients. Several variables have to be taken into account in order to appropriately identify patients with severe left ventricular dysfunction who are likely to benefit from myocardial revascularization. The recovery of cardiac function can be expected only in patients with sufficiently large areas of hibernating myocardium, particularly when the contractile reserve is documented. The anatomy of the coronary arteries should be suitable for coronary bypass grafting and provide a good run-off. Patients with an excessively dilated heart, with signs and symptoms of right heart failure and significant pulmonary hypertension are not candidates for myocardial revascularization. An appropriate surgical strategy, also including the reduction of the left ventricular volume and/or the correction of mitral insufficiency if needed, is the key factor for a successful revascularization procedure in patients with coronary artery disease and heart failure as the predominant symptom.