Outpatient coronary angiography using 7 French catheters in Singapore.

PURPOSE: Out-patient coronary angiogram (OCA) is commonly performed in many centres using 5 or 6 French (F) catheters. Though this small catheter may reduce bleeding complications, manipulatability and adequate vessel visualisation are problems which may increase procedure time. 7 or 8 F catheters have been used in Caucasians. We report our experience with OCA using 7 F catheters in an Asian centre. METHODS: Sixty-six patients with low procedural risk were consecutively recruited. They were pre-medicated with oral diazepam. Selective coronary angiogram (SCA) and left ventriculogram were performed via the femoral artery. Parenteral heparin was administered after the arterial puncture. After the procedure, haemostasis was secured by at least ten minutes of manual compression. The patients were immobilised for six hours and thereafter encouraged to walk for about an hour. The groin was inspected by a doctor before discharge and reviewed the following day. RESULTS: The age ranged from 27 to 73 years with a mean of 52.6. There were 48 men and 18 women. Seventeen patients had previous SCA or angioplasty. There was no significant coronary artery disease (CAD) in 26 patients (39.4%). Thirteen patients (19.7%) had minor CAD, 20 (30.3%) had single or double vessel and 7 (10.6%) had triple vessel disease. The mean procedural time was 16.6 +/- 7.3 minutes, ranging from 7 to 54. Seven (10.6%) of the patients had a small haematoma prior to discharge. None of the haematoma deteriorated at review. We did not find sex, age, history of diabetes mellitus or hypertension, height, weight, body mass index, use of anti-platelet agents, systolic blood pressure at and after the procedure and coronary artery anatomy to be associated with an increased risk of haematoma. The estimated cost savings for a non-subsidized patient was S$285 and for a subsidized patient was S$66. CONCLUSION: We conclude that OCA using 7 F catheters is a safe and efficacious procedure in our patients.

[Pacemaker syndrome and retrograde ventriculoatrial conduction].

19 cases of pacemaker syndrome were observed in 121 patients implanted with VVI pacemakers. The main manifestations of pacemaker syndrome were dizziness, lightheadedness, fatigue, hypotension and congestive cardiac failure after permanent ventricular pacing. The incidence of pacemaker syndrome was 20% in patients with sick sinus syndrome and 13.2% with A-V block. Pacemaker ECG showed retrograde ventriculoatrial conduction in 25 of 121 cases. Among these patients, 14 (56%) had pacemaker syndrome, while only 5 of 96 cases without ventriculoatrial conduction had this syndrome, so the incidence of the two groups were quite different, P less than 0.0001. The frequency of ventriculoatrial conduction in patients with sick sinus syndrome was higher than in patients with A-V block (16/45 vs 9/76, P less than 0.05). The electrophysiologic study were performed in 17 cases before PM implantation. 3 cases had 170-190 ms ventriculoatrial 1:1 conduction. Retrograde ventriculoatrial conduction in pacemaker ECG were present during ventricular pacing in all of them.

Myocardial perfusion imaging with technetium-99m sestamibi SPECT in the evaluation of coronary artery disease.

Technetium-99m hexakis-2-methoxy-isobutyl-isonitrile (99mTc sestamibi) has been used for myocardial perfusion imaging in the evaluation of coronary artery disease (CAD) since 1990. The experience of its use in an Asian population with and without previous myocardial infarction (MI), diabetes mellitus (DM), hypertension (HPT) and collateral circulation (COL) is reported. One hundred and thirty-nine patients who underwent treadmill exercise testing with 99mTc sestamibi single photon emission computed tomography (SPECT) and coronary angiogram were studied. The overall sensitivity for the detection of CAD was 91.0% and specificity was 64.7%. For patient without previous myocardial infarction, the sensitivity was 83.8% and specificity was 83.3%. Patients with COL had a higher sensitivity while those with HPT had a lower specificity. Sensitivity was higher in patients with multi-vessel disease (MVD) than single vessel disease (SVD). The overall detection for individual artery stenosis was 74.1% with a specificity of 73.1%. Amongst the three major coronary arteries, sensitivity was highest for the right coronary artery and specificity was highest for the left circumflex artery. Specificity was higher in patients without MI or COL. We found that the agreement between 99mTc sestamibi SPECT and coronary angiogram for the extent of CAD was only 52.5%. The concordance rate was higher for patients with MVD than SVD. It is concluded that 99mTc sestamibi SPECT is a sensitive and specific test for the detection of CAD and localization of disease to individual coronary arteries in our patients with some differences in the subgroups. Agreement between coronary angiogram and 99mTc sestamibi for the extent of coronary artery disease was also satisfactory.