Auricular fibrillation without other evidence of heart disease; a cause of reversible heart failure

Duration of atrial fibrillation and imminence of stroke: the Framingham study

The role of Atrial Fibrillation (AF) as a precursor of stroke was examined in the Framingham cohort based on 30 years of follow-up during which time 501 strokes occurred. There were 59 persons who sustained stroke in association with AF excluding those with rheumatic heart disease. AF increased the risk of stroke five-fold and the excess risk was found to be independent of the frequently associated cardiac failure and coronary heart disease. The contribution of AF to stroke risk was also at least as powerful as that of the other cardiovascular precursors. Stroke associated with AF was not only independent and substantial but also imminent. There was a distinct clustering of stroke events at the time of onset of the AF. Thirty day case-fatality rates were no different in those with strokes accompanied by AF than not at 17% versus 19% respectively. Recurrences in those with AF were only slightly more frequent, 25% versus 20%, a difference that was not statistically significant. Stroke recurrence in the first 6 months following initial stroke was more than twice as common (47% versus 20%) in the AF group.

Electroconversion of dysrhythmias. Past experience and future indications

A follow-up of our first 100 electroconversion procedures is presented. Our method, results and complications are compared with those reported in other series. The future place of electroconversion in the management of acute and chronic arrhythmias is discussed.

Atrial Fibrillation in Flying Personnel

Sixty cases of atrial fibrillation from the USAF flying population are reported. Follow-up information in 59 subjects averaged 41.2 months.

Only three cases of persistent atrial fibrillation were detected and two of these had normal sinus rhythm prior to the onset of atrial fibrillation.

There were 21 cases of recurrent paroxysmal atrial fibrillation and 36 cases of isolated acute atrial fibrillation associated with a variety of precipitating factors. Thyrotoxicosis was notable by its absence in any of these cases of atrial fibrillation.

Symptomatology either related to the primary disorder precipitating atrial fibrillation or secondary to the arrhythmia itself was frequently observed.

The hemodynamic effects of atrial fibrillation on cardiac output, and cerebral artery spasm with diminished cerebral blood flow are important aeromedical considerations.

Ventricular dynamics in atrial fibrillation

During atrial fibrillation there are beat-to-beat changes of ventricular rate, end-diastolic volume, end-diastolic pressure, and arterial pressure or resistance to ventricular ejection. The effect of these variables on left ventricular dynamics in man has been approached by studying single sequences of beats in patients with atrial fibrillation. An index of changes of left ventricular volume has been determined from the electrokymogram of left cardiac border. Left ventricular pressures have been measured at surgery or by the transbronchial technic. These studies provide a better understanding of the hemodynamics of the left ventricle during atrial fibrillation and demonstrate another approach to the study of left ventricular function in man.