Subocclusion of the Sinus Node Artery During Coronary Angioplasty: Arrhythmological Considerations

We report the case of a 58‐year‐old man who developed atrial fibrillation as a result of iatrogenic subocclusion of a diseased sinus node artery, originating from the left circumflex artery (LCx), occurring during LCx stenting, suggestive of an ischemic etiology of sinus node dysfunction. Copyright © 2010 Wiley Periodicals, Inc.     

Association of Regional Wall Shear Stress and Progressive Ascending Aorta Dilation in Bicuspid Aortic Valve

ObjectivesThe aim of this study was to evaluate the role of wall shear stress (WSS) as a predictor of ascending aorta (AAo) growth at 5 years or greater follow-up.BackgroundAortic 4-dimensional flow cardiac magnetic resonance (CMR) can quantify regions exposed to high WSS, a known stimulus for arterial wall dysfunction. However, its association with longitudinal changes in aortic dilation in patients with bicuspid aortic valve (BAV) is unknown.MethodsThis retrospective study identified 72 patients with BAV (age 45 ± 12 years) who underwent CMR for surveillance of aortic dilation at baseline and ≥5 years of follow-up. Four-dimensional flow CMR analysis included the calculation of WSS heat maps to compare regional WSS in individual patients with population averages of healthy age- and sex-matched subjects (database of 136 controls). The relative areas of the AAo and aorta (in %) exposed to elevated WSS (outside the 95% CI of healthy population averages) were quantified.ResultsAt a median follow-up duration of 6.0 years, the mean AAo growth rate was 0.24 ± 0.20 mm/y. The fraction of the AAo exposed to elevated WSS at baseline was increased for patients with higher growth rates (>0.24 mm/y, n = 32) compared with those with growth rates <0.24 mm/y (19.9% [IQR: 10.2%-25.5%] vs 5.7% [IQR: 1.5%-21.3%]; P = 0.008). Larger areas of elevated WSS in the AAo and entire aorta were associated with higher rates of AAo dilation >0.24 mm/y (odds ratio: 1.51; 95% CI: 1.05-2.17; P = 0.026 and odds ratio: 1.70; 95% CI: 1.01-3.15; P = 0.046, respectively).ConclusionsThe area of elevated AAo WSS as assessed by 4-dimensional flow CMR identified BAV patients with higher rates of aortic dilation and thus might determine which patients require closer follow-up.     

经皮腔内冠状动脉成形术中冠状动脉阻塞对心率变异性的影响

对冠脉造影确诊冠心病而行经皮腔内冠状动脉成形术（PTCA）治疗的20例患者，采用心率变异性（HRV）频域法分析PTCA术球囊充气冠脉阻塞前、后患者的HRV，以评价PTCA米冠脉急性闭塞时心脏自主神经功能状况的变化，及与冠脉阻塞部位的关系。其中前降支组13例，右冠状动脉组7例。结果表明；PTCA术冠状动脉阻塞时前降支组HRV指标中的低频段（LFP）显著增高（267．36±21．30升至341．19±26．42bpm2／Hz，P＜0．05），说明HRV降低，右冠状动脉组的HRV虽有所增大，但未达统计学意义（P＞0．05）。提示PTCA术中HRV的变化可能与球囊扩张冠脉部位有关。     

Intracoronary Nitrogylcerin and Regional Coronary Blood Flow Responses During Coronary Angioplasty in Patients

To examine the direct effects of nitroglycerin (NTG) on anterior regional coronary blòod flow, electrocardiographic and hemodynamic responses were measured immediately before, during, and after brief coronary occlusion in 17 patients undergoing left anterior descending coronary angioplasty (PTCA). Hemodynamic data and the time from the onset of coronary occlusion to 1.0 mm ST elevation or depression were compared for matched control and NTG occlusion periods. Ten seconds before the "NTG" occlusion, 200 μg of NTG was injected into the left coronary artery. Baseline and occlusion level great cardiac vein flow (thermodilution) was similar for both occlusion periods (93 ± 27 to 59 ± 23 mL/min for control; 95 ± 27 to 56 ± 22 mL/min for NTG occlusion). NTG reduced mean arterial pressure (91 ± 11 to 82 ± 15 mmHg, P < 0.05) during increased basal great vein flow (95 ± 27 to 127 ± 54 mL/min p < 0.01) immediately prior to occlusion. Great vein hyperemic flow after release of occlusion increased 21 ± 30% versus 36 ± 40% (P = ns) after control occlusion. There were no differences in heart rate or systolic-heart rate pressure products, time to ischemic ST-T wave changes or the maximal hyperemic responses from the control occlusion. These data suggest that during the initial minutes of coronary occlusion, the marked but transient coronary vasodilation induced by intracoronary NTG does not significantly modulate myocardial ischemia or regional coronary blood flow responses. The clinical benefits of NTG during PTCA most likely occur more through other mechanisms than direct myocardial flow augmentation. (J Interven Cardiol: 1988:1:1)     

Thrombin Generation and Activity During Coronary Angioplasty: Influence of Angiographic Lesion Morphology

OBJECTIVE: To investigate the relationships between coronary atherosclerotic plaque injury, lesion morphology, and activation of the coagulation cascade. BACKGROUND: Balloon angioplasty of coronary lesions may result in intracoronary thrombin generation and activity. It is unknown whether the angiographic morphology of the lesion prior to intervention, an indicator of the presence of thrombus in the lesion, is a determinant of the degree of coagulation cascade activation. METHODS AND RESULTS: Biochemical markers of thrombin generation (prothrombin fragment F1+2) and thrombin activity (fibrinopeptide A; FPA) were measured in coronary blood before, 1 and 10 minutes after percutaneous transluminal coronary angioplasty (PTCA) in 24 patients with an angiographically complex lesion morphology and 24 patients with an angiographically simple lesion morphology. Using previously defined criteria, 18 of the 48 patients (38%) demonstrated a significant rise in coronary plasma F1+2; 8 of these 18 (44%) had simple and 10 of 18 (55%) had complex angiographic lesion morphologies (p=NS). With respect to thrombin activity, 15 of the 48 patients (31%) demonstrated a significant rise in coronary plasma FPA; 7 of these 15 patients (47%) had a simple lesion morphology and 8 (53%) had a complex morphology (p=NS). When analyzed as a group, patients with complex lesion morphologies demonstrated a small elevation in coronary plasma levels of FPA 10 minutes post-PTCA (median 3.2 ng/ml, 95% CI 2.4D5.8 ng/ml) in comparison to the levels measured proximal to the lesion pre-PTCA (median 2.1 ng/ml, 95% CI 1.6D3.5 ng/ml; p=0.05). In contrast, in the group of patients with simple lesion morphologies, the plasma FPA levels proximal to the lesion pre-PTCA (median 2.1 ng/ml, 95% CI 1.5 to 3.9 ng/ml) were similar to those measured 10 minutes after the procedure (median 2.0 ng/ml, 95% CI 1.5 to 6.3 ng/ml; p=NS). CONCLUSIONS: In comparison to patients with angiographically complex lesions, patients with angiographically simple lesions demonstrate a similar incidence (~33%) of elevated coronary plasma thrombin generation (F1+2) and activity (FPA) after PTCA. As a group, patients with angiographically complex lesions (irregular borders, overhanging edges, filling defects) demonstrate a slightly greater increase in thrombin activity in comparison to patients with simple lesion morphologies. Percutaneous coronary interventions of lesions with a wide variety of angiographic morphologies are prone to result in activation of the coagulation cascade.     

合并升主动脉钙化的冠心病患者不用主动脉侧壁钳非体外循环冠状动脉多支搭桥

目的:总结不用主动脉侧壁钳的非体外循环冠状动脉多支搭桥治疗合并升主动脉钙化的冠心病病人的临床经验。方法:不用主动脉侧壁钳的非体外循环冠状动脉搭桥(OPCAB)30例,男23例,女7例,年龄53～83岁,平均69.1岁。有脑中风史13例。双支和三支系统病变为2例和28例,同时有左主干病变11例。左心室射血分数0.52±0.19。30例病人均可以摸到明显的升主动脉片状或弥漫性钙化斑块,21例病人手术中食道超声心动图提示主动脉明显钙化。9例以左乳内动脉(LIMA)为唯一供血来源(in-flow),其余静脉桥吻合到LIMA,1例静脉桥吻合到无名动脉,其余静脉～静脉"Y"吻合,6例使用主动脉隔离装置(Enclose)行主动脉上的近端吻合,14例采用双侧乳内动脉。术中用血流仪定量测定桥血流。结果:本组30例人均远端吻合3.40(3～5)处。术后8例需多巴胺>5ng/(kg·min)支持16～45小时。手术后2～12小时病人完全清醒,人均带气管插管时间(8.9±3.7)小时。手术中实时桥血流测定显示桥血流均满意(17～110ml/ min),9例以LIMA为唯一in-flow,LIMA总血流量基本是各分支桥血流量之数学和。无围手术期心肌梗死、无出血再开胸、无脑中风,无手术后急性肾衰。下肢切口感染1例,8例(26.7%)术后一过性房颤。全组无围手术期死亡。术后心绞痛均消失,术后(12.7±4.6)天出院。结论:在升主动脉有明显钙化的冠心病病人,采用OPCAB结合主动脉不接触(no-touch)技术或主动脉近端吻合装置,安全可行,临床效果满意。     

QRS Changes During Percutaneous Transluminal Coronary Angioplasty and Their Possible Mechanisms

Objectives. The purpose of the study was to describe the configuration, and investigate the mechanisms, of QRS changes occurring during percutaneous transluminal coronary angioplasty (PTCA).Background. QRS changes during PTCA have been attributed to both a passive ST segment shift and conduction disturbances (peri-ischemic block). The direct relation between ST segment shift and QRS changes, however, has not been established, and the definition of conduction disturbances remains to be clarified.Methods. Twelve-lead electrocardiograms (ECGs) were recorded before PTCA, at the end of 2 min of PTCA and after return to baseline values in 29 patients (left anterior descending coronary artery [LAD] in 13 patients, right coronary artery [RCA] in 14 and left circumflex coronary artery in 2). Electrocardiographic complexes before and during PTCA were superimposed to determine the amplitudes of initial, terminal and total QRS deflection; the relations of QRS changes to baseline (TP segment) and ST segment shift; and the duration of QRS and corrected QT intervals.Results. 1) The direction of the initial QRS deflection was unchanged, but changes of its amplitude occurred. 2) Terminal QRS deflection changed in all patients with a ST segment shift >17% of the R amplitude, and the correlation between the decrease in the S amplitude and ST segment shift was significant (r = 0.9, p < 0.01) in patients with LAD PTCA. Correlation between changes in total QRS amplitude and ST segment shift in patients with RCA PTCA was weaker (r = 0.54, p = 0.056). 3) Transient conduction disturbance manifested by QRS widening in selected leads occurred in 2 of 29 patients.Conclusions. 1) Changes in terminal QRS deflection during PTCA are proportional to the magnitude of the ST segment shift. 2) Conduction disturbances manifested by increased QRS duration occurred infrequently. We suggest that the term peri-ischemic block be applied only to changes in QRS configuration associated with QRS widening.     

The Relationship Between Intimal Tears During Coronary Angioplasty and Fibrinopeptide A

Arterial injury during routine percutaneous trans-luminal coronary angioplasty (PTCA) may stimulate clotting mechanisms. Excessive (i.e., angiographically visible) arterial trauma might accordingly predispose to a greater tendency for thrombosis. This study evaluates whether arterial trauma (i.e., angiographically visible intimal tears and arterial dissections) is related to evidence of active thrombosis. Fibrinopeptide A (FPA), a sensitive marker of thrombin activity, was measured in 79 patients undergoing elective PTCA immediately following angioplasty, as well as prior to hospital discharge (mean 2 days post-PTCA). Levels > 2.0 ng/mL were considered elevated. Intimal tears were visualized in 41 patients. Of these 41, 31 had elevated FPA levels (sensitivity = 0.76). This association between FPA elevation and intimal tears was significant (P = 0.033). Of the remaining 38 patients without intimal tears, 20 had elevated FPA levels (specificity = 0.47). Concomitant arterial dissection, as well as an intimal tear, was found in four patients with elevated FPA and in one patient with normal FPA. Conclusion. Arterial trauma during PTCA is accompanied by a greater degree of ongoing thrombosis. Although FPA elevation was not specific for intimal tears, a highly significant association with intimal tears was observed. Further study may yield even more specific hematologic parameters on ongoing early thrombosis following PTCA, particularly in patients with intimal tears. (J Interven Cardiol 1989:2:3)     

主动脉缩窄介入治疗的现状和进展

随着介入器材的发展和介入技术的成熟,球囊成形术和支架置入术已代替外科手术成为主动脉缩窄的首选治疗方式,现综述近年来主动脉缩窄介入治疗的研究进展和治疗效果。     

Application of an Electrocardiographic Inverse Solution to Localize Ischemia During Coronary Angioplasty

Localization of Ischemia. This study demonstrates the utility of an electrocardiographic Localization of Ischemia. This study demonstrates the utility of an electrocardiographic Inverse solution, coupled with body surface potential mapping (BSPM), in localizing acute ischemia in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). PTCA balloon inflations produce complete occlusion and acute transient ischemia, which can be detected electrocardiographically with BSPM. Comparisons between maps recorded both during and before the inflation of the PTCA balloon allow patient- and artery-specific characterizations of the resulting ischemia. Knowledge of the patient's coronary anatomy and the location of the occlusion site by coronary angiography permit an estimation based on cardiac hemodynamics of the region of myocardium most likely to suffer from PTCA-induced ischemia. Electrocardiographic inverse solutions provide a means of predicting cardiac potentials from body surface maps. In this study, we describe an inverse solution we have developed to localize the transient ischemia produced by PTCA. To validate the procedure, we compared the locations of predicted ischemia in seven patients with a qualitative estimate of the perfusion region based on fluoroscopic examination of each patient's coronary anatomy and PTCA balloon location. In each case, the region of ischemia predicted by the model included the perfusion zone determined fluoroscopically. These results suggest that electrical changes induced by acute ischemia can be localized with an electrocardiographic inverse solution.     

Balloon Angioplasty for Native Coarctation of the Aorta: Acute and Mid-Term Results

BACKGROUND: Balloon angioplasty is an accepted treatment for recurrent coarctation of the aorta. Application of this technique to patients with native coarctation is controversial. OBJECTIVE: To report on the immediate and mid-term results of this procedure in patients with native coarctation, including infants <6 months of age. METHODS AND RESULTS: Twenty-four children underwent balloon angioplasty of their coarctation at a median age of 2 yr. (range 2 weeksD14.7 yr.) and median weight of 13 kg (range 3D64 kg). The mean peak systolic gradient across the coarctation decreased from 40 +/- 14 to 9 +/- 6 mmHg (p < 0.001) and the mean diameter of the narrowest area improved from 4.1 +/- 2.1 to 7.5 +/- 2.5 mm (p < 0.001). Four patients had recurrence of their coarctation, 3 of whom were < 3 months of age. Two of these patients had successful repeat dilation. At a mean follow-up interval of 2.4 +/- 1.7 years, one patient (4%) developed an aneurysm. Three patients underwent surgical repair (two for recurrence and one for resection of the aneurysm). The remaining patients (87.5%) are normotensive with mean peak systolic gradient between the right arm and the lower extremity of 4 +/- 9 mmHg. CONCLUSION: Balloon angioplasty for native coarctation is an effective and safe method for most patients with coarctation. Repeat dilation is possible and surgical repair of an aneurysm is safe.