ABSTRACT
Modification of atrioventricular node is a usual and necessary operation to cure atrioventricular nodal reentrant tachycardia (AVNRT). In this operation, atrioventricular block is the most severe complication and its prevention is of our great concern. This complication always occurs under some special circumstances with potential risk. So, it is very important to realize such conditions, as in this paper. A patient with paroxysmal palpitation for 10 years, aggravating to shortness of breath with chest distress for 1 year; cardiac electrophysiological examination found slow conduction in both antegrade and retrograde paths of reentrant loop, and typical AVNRT could be induced. During effective ablation there was no junctional rhythm. In some special cases, modification of atrioventricular node should not only rely on the junctional rhythm to determine the ablation effect, but also on the time of cardiac electrophysiological examination, as such to avoid the severe complication of atrioventricular block caused by excessive ablation.
ABSTRACT
OBJECTIVE: To investigate the effect of emergency percutaneous coronary interventional (PCI) treatment on plasma brain natriuretic peptide (BNP) levels and left ventricular remodeling in patients with acute myocardial infarction (AMI). METHODS: This study included 118 patients with AMI and 20 healthy volunteers (their results were regarded as normal reference). Fifty-two patients who underwent successful emergency PCI 6-12 hours after onset were named as PCI group, and 66 patients rejected or in whom emergency PCI failed served as the control group. Plasma BNP levels were determined with Triage rapid assay at admission,at 12, 24, 48, 72 hours and 7, 14, 28 days after admission for both groups. Left ventricular ejection function (LVEF) was assessed by echocardiography with the modified Simpson's equation on 3-5 days and 28 days. Same assay was performed for 20 healthy volunteers. RESULTS: Plasma BNP levels of both groups were significantly higher at admission than those of volunteers. There was significant difference in BNP levels between two groups at corresponding time points (all P<0.01). In PCI group, BNP level peaked during 12-24 hours after admission, whereas two peaks of elevation of BNP levels were detected in control group, the first peak appeared during 12-24 hours and the second peak on 7 days after admission. Plasma BNP levels in PCI group were significantly lower than those of control group at corresponding time points (all P<0.01). There was no difference in LVEF level between two groups on 3-5 days after admission. LVEF level after emergency PCI was significantly higher than that of control group on 28 days after admission (P<0.01). CONCLUSION: Emergency PCI lowers plasma BNP level and improve LVEF level in patients with AMI, and it may reverse ventricular remodeling.
Subject(s)
Angioplasty, Balloon, Coronary , Myocardial Infarction/blood , Natriuretic Peptide, Brain/blood , Ventricular Remodeling , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Myocardial Infarction/physiopathology , Myocardial Infarction/therapyABSTRACT
OBJECTIVE: To evaluate the cardiac angiogenesis after percutaneous myocardial laser revascularization (PMR). METHODS: The left anterior descending coronary arteries of 10 healthy mongrel dogs weighing 14 - 18 kg were ligated partially so as to construct a model of chronic cardiac ischemia. Then the dogs were randomly divided into 2 groups of 5 dogs: PMR and control groups. Cardiogenesis Holmium: YAG laser system was used to make endomyocardial channels (15 +/- 3 channels/dog) in the ischemic ventricular walls in PMR group 2 weeks after the ligation. Sham procedure was conducted on the control group. Myocardial perfusion was examined by single photon emission computed tomography (SPECT) and left ventricle ejection fraction (LVEF) was examined by cardiac ultrasound before the ligation and 1, 4, and 12 weeks after PRM in the PMR group and before and 3, 6, and 14 weeks after the ligation in the control group. In the PRM group one dog was killed after the SPECT and LVEF examination 1 and 4 weeks after the PRM respectively and the remaining 3 dogs were killed after the SPECT and LVEF examination 12 weeks after the PRM. The dogs in the control group were killed after the SPECT and LVEF examination 14 weeks after the ligation. Myocardial pathology and cardiac angiogenesis analysis were conducted in both groups. RESULTS: Three months after PMR or coronary artery ligation, the SPECT scores of the PMR and control groups decreased from 3.2 +/- 0.6 and 3.1 +/- 0.5 to 0.3 +/- 0.2 and 1.2 +/- 0.3 respectively (both P < 0.05), the LVEF of the 2 groups increased from 42.6 +/- 6.5 and 43.2 +/- 8.7 to 55.8 +/- 7.6 and 42.6 +/- 6.5 respectively (both P < 0.05). Microscopy showed that the amount of micrangii was 45.6 +/- 7.4 vessel/field in the PMR region of the PRM group, significantly much more than that in the non-ischemic region of the PRM group (18.2 +/- 4.7), the ischemic region of the control group (21.4 +/- 5.6), and the non-ischemic region of the control group (17.3 +/- 6.9, all P < 0.05). CONCLUSION: PMR promotes angiogenesis in the ischemic myocardial wall, thus improving the blood perfusion of ischemic myocardium and global cardiac systolic function.
