Subject(s)
Coronary Artery Bypass , Kidney Transplantation/adverse effects , Myocardial Infarction/surgery , Postoperative Complications/surgery , Cadaver , Female , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/surgery , Middle Aged , Myocardial Infarction/etiology , Time FactorsABSTRACT
We reported 2 patients with complete A-V block with a DDD pacemaker whose exercise capacity was increased by decreased ventricular tracking limit rate setting (VTL) of their pacemakers. Cardiopulmonary exercise test was used for estimating exercise capacity. Case 1: A 15-year-old girl complained of fainting. Her electrocardiogram (ECG) revealed complete A-V block (atrial rates 100/min, ventricular rates 39/min). After implantation of a DDD pacemaker and the VTL setting at 152/min, her bradycardia disappeared, however, she complained of dyspnea after a few minutes' walk. We performed symptom-limited cardiopulmonary exercise test with a motor-driven treadmill. When the pacing rate reached VTL (152/min), ECG suddenly changed to approximately 2:1 pacing (80/min) and the patient complained of dyspnea. Concomitant rapid increases in VE, VCO2 and RQ suggested that dyspnea was caused by the marked change in pacing rates on VTL. With the lowered VTL (110/min), there was no rapid increase in VE, VCO2 and RQ, and dyspnea subsided when the pacing rate reached VTL. At the same time, the peak VO2 and exercise time were increased by 15% and 8%, respectively. Case 2: A 47-year-old man complained of syncope. His ECG revealed complete A-V block (atrial rates 100/min, ventricular rates 33/min). After a DDD pacemaker implantation (VTL: 150/min), he experienced dyspnea while walking up the stairs in his office. Like in Case 1, when the VTL was lowered from 150/min to 110/min, both the peak VO2 and exercise time were increased by 11%.(ABSTRACT TRUNCATED AT 250 WORDS)
Subject(s)
Cardiac Pacing, Artificial/methods , Exercise Test , Heart Block/therapy , Adolescent , Electrocardiography , Female , Humans , Male , Middle Aged , Pacemaker, ArtificialABSTRACT
T1-201 stress myocardial scintigraphy was performed in 35 cases of ischemic heart disease (angina pectoris and myocardial infarction) to assess the accuracy of SPECT and bull's eye display in the quantitative diagnosis of coronary artery lesions. We evaluated the sites of ischemic heart disease using the following methods: 1. SPECT (visual): visual evaluation by myocardial SPECT images. 2. SPECT +bull's eye (visual): visual evaluation by stress, delayed and washout images of bull's eye display. 3. bull's eye (quantitative): quantitative evaluation by the washout rate and % uptake. The diagnostic accuracy of method 2 was higher than that of method 1 in all coronary arterial vessels; LAD (74% vs 80%), LCX (60% vs 63%) and RCA (57% vs 60%). The diagnostic accuracy of method 3 was approximately equal to that of method 2. The diagnostic accuracy of method 2 was higher than of method 1 in patients with three-vessel disease (43% vs 67%), while there was no such difference in patients with both single and two-vessel disease. Moreover, the diagnostic accuracy of method 3 was approximately equal to that of method 2 in patients with three-vessel disease. In some cases the redistribution was recognized only by using washout images or by calculating the washout rate as a quantitative evaluation. In conclusion, the bull's eye display improved the diagnostic accuracy of T1-201 scintigraphy, but the quantitative analysis did not further improve the accuracy. However, there were some possibilities of evaluating the redistribution in some cases by using quantitative analysis.(ABSTRACT TRUNCATED AT 250 WORDS)
