摘要:

The ventricular response in atrial fibrillation is determined by the long refractory period of the AV junction. Since an atrial impulse is always available for transmission to the ventricles, a regular ventricular rhythm would be expected, the rate of which would reflect the duration of a stable junctional refractory phase. The irregularity of the ventricular action associated with atrial fibrillation, therefore, indicates changes of refractoriness of the AV junctional tissues from cycle to cycle. This can best be attributed to varying degrees of penetration of “blocked” atrial impulses into parts of the AV junction, and to the effect of such concealed conduction on the propagation of subsequent impulses.The following facts are pointed out and illustrated as evidence of concealed AV and VA conduction during atrial fibrillation: (a) Occurrence of a “compensatory pause” following a ventricular premature systole. (b) Failure of an AV nodal escape to appear at the expected time due to concealed discharge of a subsidiary AV nodal pacemaker by a penetrating atrial impulse. (c) Acceleration of the ventricular rate when atrial fibrillation changes to flutter (elimination of concealed conduction with slowing of the atria). (d) A tendency for two or more long cycles to occur in succession (each containing one or more concealed responses).The reasons for the variations of the refractory period at different levels of the AV junction as a result of concealed conduction are analyzed. Their complex interplay may readily account for the over-all irregularity of the ventricular response associated with atrial fibrillation.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

A series of four patients who died following rupture of the ventricular septum due to myocardial infarction has been reported. One of these died of hemorrhage due to a defective clotting mechanism 8 hours after successful surgical repair.The 13 cases of surgical repair of postinfarction ventricular septal defect reported by other authors are reviewed.The time interval is important and preferably 3 to 6 months should elapse following myocardial infarction before surgery is undertaken.Surgery should be considered in every patient diagnosed as having an acute septal rupture following myocardial infarction who fails to respond to vigorous medical treatment.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

Three cases with pulmonary stenosis, intact ventricular septum, and right aortic arch are presented, along with physiologic data. Two cases had infundibular stenosis and, in addition, an aberrant left subclavian artery. The third case was thought to have valvular stenosis. All three patients have been successfully operated upon and show good clinical results.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

The mitral valve anatomy of endocardial cushion defects is reviewed and compared with the anatomic requirements for normal mitral valve function. It is shown that very often mitral valve anatomy is such that function should be not at all or only minimally affected. Evidence is quoted that this is indeed so.The potential harm that may result from indiscriminate suturing of mitral valve clefts and careless repair of the septal defects is described. Principles for the repair of the mitral valve in these cases are enunciated. A small series of cases that have had preoperative and 1-year postoperative assessments of mitral valve function is presented to illustrate some of these points.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

A Starr-Edwards mitral valve of orifice area 1.53 cm.2was successfully inserted to replace[see figure in the PDF file][see table in the PDF file]a “parachute” mitral valve producing clinically significant mitral stenosis.

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:1965

数据来源: OVID