Search

A prospective study was conducted to evaluate how many patients maintain sinus rhythm after DC cardioversion of atrial arrhythmias and to assess factors predictive of long-term success. The study group consisted of 61 patients (45 men, 16 women) aged 18-88 years (mean age 66 +/- 11 years) who undervent cardioversion, at the Department of Cardiology, Landspitalinn, from October 1990 to June 1992. Prior to cardioversion data were collected on the patient's medical history, medications, heart size on chest X-ray, and echocardiographic findings. Overall, 41 (67.2%) patients were in atrial fibrillation while 20 (32.8%) had atrial flutter. Sinus rhythm was restored by DC cardioversion in 47 (77%) patients, none of whom experienced an embolic event prior to discharge. Patients with atrial flutter had a higher conversion rate (95%) than those in atrial fibrillation (68.3%) (p=0.024) and also those who had had an atrial arrhythmia for less than one week (94.4%) in comparison to patients with an arrhythmia of longer or unknown duration (69.8%) (p-0.047). The primary success rate was not influenced by heart size on chest X-ray or echocardiographic variables. The study aimed to follow the patients for one year after cardioversion. Of the 47 patients who converted to sinus rhythm data are available on 44 for a mean follow-up of 11 +/- 3 months (range 1-14 months), at which time 25 (57%) still remained in sinus rhythm. Heart size on chest X-ray was significantly increased in the group that did not maintain sinus rhythm (p=0.03), and their left atrial size on echocardiography was slightly increased (p=0.10). Patients who originally had atrial flutter were more likely to remain in sinus rhythm than those who had been in atrial fibrillation (p=0.12), as did those who had had the arrhythmia for less than one week prior to cardioversion compared to those who had a longer or unknown duration (p=0.11). We conclude, that DC cardioversion can be attempted in most patients with atrial flutter or fibrillation. However, clinical factors, heart size on chest X-ray and echocardiographic findings should be considered before deciding to perform DC cardioversion.

Atrial fibrillation is an increasing health care problem and the incidence of this arrhythmia is expected to increase substantially in the next two decades. Atrial fibrillation can be seen in patients with structural heart disease as well as those who have a normal heart. A variety of underlying mechanisms can lead to atrial fibrillation, including parasympathetic stimulation causing vagal atrial fibrillation. Complications of atrial fibrillation include congestive heart failure and stroke. Atrial fibrillation is an independent risk factor for increased mortality. In recent years a number of new treatment options have emerged. Anticoagulation decreases the risk of stroke and new antiarrhythmic drugs have been developed which increase the likelihood of conversion to and subsequent maintenance of sinus rhythm. In addition there have been advances in the approach to electrical cardioversion. Radiofrequency ablation therapy is a promising option in the treatment of atrial fibrillation and could be increasingly utilized in the near future. This paper focuses on advances in the therapy of atrial fibrillation, including new pharmacological agents, radiofrequency ablation and electrical cardioversion.

Initiation of bystander cardiopulmonary resuscitation (CPR) is directly linked to the outcome of cardiac arrest in the community. Recent reports have indicated a reluctance among witnesses to perform CPR on strangers especially mouth to mouth ventilation. The status of this in Iceland is unknown. The objective of this study was to assess the attitude of Icelanders towards bystander CPR.A telephone survey was conducted on 1200 randomly selected Icelanders, aged 16-75 years, with regard to their attitude towards pre-hospital CPR on strangers. A total of 804 (70.1%) chose to participate.A large number had received some kind of training in CPR (73%), wheras only 6% had actually participated in CPR. In accordance, 50% thought they would be able to perform chest compressions adequately and 55% mouth to mouth ventilation. A total of 491 (65%) would likely volunteer to perform chest compressions on a stranger, while 178 (24%) would not and 84 (11%) were undecided. Similarly, 473 (64%) would likely volunteer to perform mouth to mouth ventilation on a stranger. One hundred seventy seven (24%) would not and 93 (12%) were unsure. An overwhelming majority, 620 (81%) said it would not make any difference regarding their participation in CPR if the procedure was simplified and included only chest compressions but not mouth to mouth ventilation.Icelanders have a very positive attitude towards bystander CPR, over two thirds have had some kind of CPR instruction and a large majority has no aversion towards performing mouth to mouth ventilation on strangers. These results are in contrast to similar data from the United States.

We reported recently that stimulation of postjunctional alpha-2 adrenergic receptors prolongs the action potential durations (APD) of isolated canine Purkinje fibers. With standard microelectrode techniques, we examined the ionic mechanism through which alpha-2 adrenergic stimulation prolonged Purkinje APD, by measuring the effects of inhibitors of the various plateau currents on the alpha-2-mediated prolongation of APD. The alpha-2-specific agonist UK 14,304 (0.1 microM) prolonged the Purkinje APD at 50% repolarization and the APD at 90% repolarization, and these effects were inhibited by yohimbine (0.1 microM). The Purkinje APD at 50% repolarization and the APD at 90% repolarization were prolonged significantly with the transient outward potassium current inhibitor 4-aminopyridine (1 mM), the rapid component of delayed rectifier potassium current inhibitor d-sotalol (10 microM), the slow component of delayed rectifier potassium current inhibitor indapamide (0.1 microM) and the chloride current inhibitor mefenamic acid (10 nM) and were shortened significantly with the calcium current inhibitor nifedipine (0.3 microM). Prolongation of Purkinje APD at 50% repolarization and APD at 90% repolarization by UK 14,304 remained intact in the presence of d-sotalol, indapamide, mefenamic acid and nifedipine. All of these UK 14,304 effects were significantly reversed by yohimbine. Only in the presence of 4-aminopyridine did UK 14,304 fail to prolong Purkinje APD. The phase 1 magnitudes of Purkinje action potentials were also significantly inhibited by UK 14,304. This effect was completely abolished only in the presence of 4-aminopyridine. These results suggest that inhibition of the 4-aminopyridine-sensitive transient outward potassium current is the major ionic mechanism by which alpha-2 adrenergic stimulation prolongs Purkinje APD.

A 36-year-old male was evaluated for treatment-resistant hypertension. A high platelet count 828 x 10(9).l-1, led to the diagnosis of essential thrombocythemia (ET). Aorto-renal angiography revealed critical bilateral renal artery stenosis and coronary angiography showed three-vessel disease. Percutaneous transluminal renal angioplasty was only partially successful. The patient received a 12-week course of busulphan and subsequently the thrombocyte count decreased to 200 x 10(9).l-1. Renal angiography 12 months later showed bilateral regression of the renal artery stenosis with lowering of the blood pressure to normal levels.

A retrospective study was performed of all patients diagnosed as having pancreatic cancer in Iceland during the period 1974-85 (12 years). The incidence of the disease during the period according to this study was 10.7 per 100,000 males and 9.8 per 100,000 females, with age-adjusted world standard incidences of 9.0 per 100,000 males and 6.7 per 100,000 females. A total of 301 patients were identified; adequate information could be obtained for 281 patients, and 225 (74.8%) had the diagnosis histologically confirmed. Two hundred and five patients with adenocarcinoma were accepted for detailed analysis. Of the patients with adenocarcinoma 139 (67.8%) were diagnosed at laparotomy, and 33 of them had the tumour resected, with an operative mortality of 12.1%. The cancer was located in the head of the pancreas in 102 patients (49.8%), and in 159 (77.6%) metastases were found at the time of diagnosis. The median survival time for the patients with adenocarcinoma was 95.4 days (SD +/- 11.1 days), although there were two patients in this group who were alive 5 years after diagnosis. The median survival for the total group of 281 patients was 98.3 days (SD +/- 11.0 days), although 6 of these patients lived for more than 5 years. The percentage of histologically confirmed tumours in Iceland is high compared with many previously reported studies.

ACCF : American College of Cardiology Foundation ACS : acute coronary syndrome AHA : American Heart Association CAD : coronary artery disease CABG : coronary artery bypass grafting CKMB : creatine kinase MB isoform cTn : cardiac troponin CT : computed tomography CV : coefficient of variation ECG : electrocardiogram ESC : European Society of Cardiology FDG : fluorodeoxyglucose h : hour(s) HF : heart failure LBBB : left bundle branch block LV : left ventricle LVH : left ventricular hypertrophy MI : myocardial infarction mIBG : meta-iodo-benzylguanidine min : minute(s) MONICA : Multinational MONItoring of trends and determinants in CArdiovascular disease) MPS : myocardial perfusion scintigraphy MRI : magnetic resonance imaging mV : millivolt(s) ng/L : nanogram(s) per litre Non-Q MI : non-Q wave myocardial infarction NSTEMI : non-ST-elevation myocardial infarction PCI : percutaneous coronary intervention PET : positron emission tomography pg/mL : pictogram(s) per millilitre Q wave MI : Q wave myocardial infarction RBBB : right bundle branch block sec : second(s) SPECT : single photon emission computed tomography STEMI : ST elevation myocardial infarction ST–T : ST-segment –T wave URL : upper reference limit WHF : World Heart Federation WHO : World Health Organization Myocardial infarction (MI) can be recognised by clinical features, including electrocardiographic (ECG) findings, elevated values of biochemical markers (biomarkers) of myocardial necrosis, and by imaging, or may be defined by pathology. It is a major cause of death and disability worldwide. MI may be the first manifestation of coronary artery disease (CAD) or it may occur, repeatedly, in patients with established disease. Information on MI rates can provide useful information regarding the burden of CAD within and across populations, especially if standardized data are collected in a manner that …