Intraatrial catheter mapping of the right atrium was performed during sinus rhythm in 92 patients: Group I = 43 control patients without paroxysmal atrial fibrillation or sick sinus node syndrome; Group II = 31 patients with paroxysmal atrial fibrillation but without sick sinus node syndrome; and Group III = 18 patients with both paroxysmal atrial fibrillation and sick sinus node syndrome. Atrial electrograms were recorded at 12 sites in the right atrium. The duration and number of fragmented deflections of the atrial electrograms were quantitatively measured. The mean duration and number of fragmented deflections of the 516 atrial electrograms in Group I were 74 +/- 11 ms and 3.9 +/- 1.3, respectively. The criteria for an abnormal atrial electrogram were defined as a duration of greater than or equal to 100 ms or eight or more fragmented deflections, or both. Abnormal atrial electrograms were observed in 10 patients (23.3%) in Group I, 21 patients (67.7%) in Group II and 15 patients (83.3%) in Group III (Group II versus Group I, p less than 0.001; Group III versus Group I, p less than 0.001). The mean number of abnormal electrograms per patient with an abnormal electrogram was 1.3 +/- 0.7 in Group I, 2.5 +/- 1.9 in Group II and 3.5 +/- 2.5 in Group III (Group I versus Group II, p less than 0.01; Group II versus Group III, p less than 0.05). A prolonged and fractionated atrial electrogram characteristic of paroxysmal atrial fibrillation can be closely related to the vulnerability of the atrial muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
Background-Prolonged and fractionated right atrial endocardial electrograms are characteristic of paroxysmal atrial fibrillation (idiopathic or associated with sick sinus syndrome). The distribution of these abnormal atrial electrograms within the right atrium and the way it is related to the likelihood that patients with sick sinus syndrome will develop paroxysmal atrial fibrillation was studied.
The manifestations of Takayasu's arteritis of the aorta were studied in 84 patients. The extent of the involvement of the aorta was classified on aortographic examination in 54 patients and from the clinical manifestations in 30. Involvement of the aorta was classified as: (1) arch type in 47 cases; (2) extensive type (whole aorta and its branches involved) in 27 cases; and (3) descending thoracic and abdominal type (only descending thoracic and abdominal aortas involved) in 10 cases. The three types resembled one another in clinical manifestations and laboratory findings except for ischemic signs which varied with the type of lesion and a slight difference in the ratio of male to female patients. Generalized, cardiac and pulmonary symptoms were noted by about two thirds of the patients in the early stage. About one third complained of local pain. The erythrocyte sedimentation rate and C-reactive protein were high values during the active stage of this disease. The hemagglutination test using tannic acid-treated erythrocytes was positive in five of seven cases. It is not clear yet that circulating anti-arterial antibodies are the direct cause of Takayasu's arteritis.
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