Differences in major limb outcomes by indication for lower extremity endovascular revascularization in patients receiving hemodialysis.

The incidence of lower extremity artery disease (LEAD) in patient receiving hemodialysis is remarkably higher than the general population. The treatment strategy and prognosis for LEAD patients differs depending on whether a patient has intermittent claudication (IC) or critical limb-threatening ischemia (CLTI). However, the distinction between the prognosis in HD-dependent patients with IC and CLTI has not been fully elucidated. This study is to determine whether indication of PAD has a distinct impact on major adverse cardiovascular and cerebrovascular events (MACCE) and limb events in patients receiving hemodialysis. The current study included 2321 prospectively enrolled patients from the Tokyo taMA peripheral vascular intervention research ComraDE registry (UMIN-CTR no. UMIN000015100) between September 2014 and December 2016. Out of the enrolled patients, 1644 were not receiving hemodialysis (non-HD patients) and 603 were receiving hemodialysis (HD patients). A composite of all-cause death, myocardial infarction, and stroke events defined as MACCE; while limb events were defined as a composite of unscheduled major amputation, unscheduled major lower limb surgery, acute limb ischemia, unscheduled endovascular treatment, and target lesion revascularization. Propensity score matching was applied among the non-HD and HD patients, in whole group, IC subgroup, and CLTI subgroup. Kaplan-Meier analysis was used for the analysis of outcomes for the whole group, IC subgroup, and the CLTI subgroup. CLTI accounted for 75.5% of the HD patients, whereas IC was 63.4% in the non-HD patients. The HD patients exhibited more frequent below-the-knee lesions than those in the non-HD patients in both IC (p = 0.01) and CLTI (p < 0.001) subgroups. Overall, HD patients exhibited a significantly higher rate of MACCE at 24 months. This trend was similar for limb events in whole group and CLTI subgroup. In contrast, no significant differences in outcomes for limb events were found in IC subgroup. Although, prognosis after EVT in HD patients were significantly worse than non-HD patients, comparable outcome with non-HD patients was observed in the patients treated for IC. Clinical trial registration: This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR No. UMIN000015100).

Femoral Vein Occlusion or Stenosis Using a Suture-Mediated Vascular Closure Device After Catheter Ablation.

A suture-mediated vascular closure device is useful for hemostasis of the femoral vein after catheter ablation; however, venous complications remain unclear. We encountered 2 cases of femoral vein occlusion and stenosis using a suture-mediated vascular closure device. Both patients underwent surgical repair and recovered venous flow. (Level of Difficulty: Intermediate.).

Predictors of the "Crosstalk" Phenomenon During Cryoballoon Ablation in Patients with Atrial Fibrillation.

Second-generation cryoballoon (CB) ablation is effective in achieving pulmonary vein (PV) isolation (PVI) in atrial fibrillation (AF) patients. The "crosstalk" (CST) phenomenon has been reported to reduce unnecessary applications during CB ablation. Nevertheless, it is unclear under what conditions the CST phenomenon occurs.To seek the predictors of the CST phenomenon during CB-guided PVI, CST phenomenon in achieving ipsilateral superior PVI during inferior PV ablation was analyzed in AF patients who underwent de novo ablation using CB. CB occlusion status and nadir balloon temperature (NT) were compared in these patients, and all ablated superior PVs were categorized into three groups according to the necessity of the touch up ablation and effectiveness of the phenomenon.Of 1082 superior PVs, 16, 40, and 1026 were classified into the CST success, CST failure, and control groups (unnecessary CST), respectively. The proportion of superior PVs ablated with complete occlusion using the CB was significantly higher in the CST success group than in the other two groups. The proportion of superior PVs ablated with NT ≤ -46°C was higher in the CST success group than in the CST failure group. The CST phenomenon was always observed if CB ablation of the superior PVs was performed with both complete occlusion and NT ≤ -46°C and was almost always ineffective if it did not meet these two criteria (sensitivity, 100%; specificity, 93%).Successful CST ablation was highly predicted if complete PV occlusion and NT ≤ -46°C during CB ablation of the superior PVs were achieved.

Optimal cut-off value of preprocedural geriatric nutritional risk index for predicting the clinical outcomes of patients undergoing endovascular revascularization for peripheral artery disease.

BACKGROUND: Malnutrition measured by the geriatric nutritional risk index (GNRI) was reported to be associated with poor prognosis for patients with peripheral artery disease (PAD). However, the optimal cut-off value of preprocedural GNRI for critical limb ischemia (CLI) and intermittent claudication (IC) is unknown. We aimed to determine its optimal cut-off value for CLI or IC patients requiring endovascular revascularization. METHODS: We explored data of 2246 patients (CLI: n = 1061, IC: n = 1185) registered in the Tokyo-taMA peripheral vascular intervention research COmraDE (TOMA-CODE) registry, which prospectively enrolled consecutive PAD patients who underwent endovascular revascularization in 34 hospitals in Japan from August 2014 to August 2016. The optimal cut-off values of GNRI were assessed by the survival classification and regression tree (CART) analyses, and the survival curve analyses for major adverse cardiovascular and limb events (MACLEs) were performed for these cut-off values. RESULTS: In addition to the first cut-off value of 96.2 in CLI and 85.6 in IC, the survival CART provided an additional cut-off value of 78.2 in CLI and 106.0 in IC for further risk stratification. The survival curve was significantly stratified by the GNRI-based malnutrition status in both CLI [high risk: 47.7% (51/107), moderate: 30.1% (118/392), and low: 10.2% (53/520), log-rank p < 0.001] and IC [high risk: 14.3% (7/49), moderate: 4.5% (29/646), and low: 0.5% (2/407), log-rank p < 0.001]. The multivariate Cox-proportional hazard analysis showed that a higher GNRI was significantly associated with a better outcome in both CLI [hazard ratio (HR) per 1-point increase: 0.97, 95% CI: 0.96-0.98, p < 0.001] and IC (HR: 0.94, 95% CI: 0.91-0.97, p < 0.001). CONCLUSIONS: Preprocedural nutritional status significantly stratified future events in patients with PAD. Given that the optimal cut-off value of GNRI in CLI was almost 10-points lower than that of IC, using a disease-specific cut-off value is important for risk stratification.

The clinical impact of the left atrial posterior wall lesion formation by the cryoballoon application for persistent atrial fibrillation: Feasibility and clinical implications.

INTRODUCTION: The left atrial (LA) posterior wall (LAPW) has been targeted to improve the clinical outcomes in patients with persistent atrial fibrillation (PersAF). This study aimed to investigate the feasibility, safety, and clinical implications of cryoballoon (CB) applications on the LAPW to accomplish electrical isolation (EI) of the LAPW with CB. METHODS: A total of 100 patients (males, 84; mean age, 64 ± 10 years) with PersAF were enrolled. The first 50 patients underwent only pulmonary vein isolation (PVI) (PVI-only group) and the remaining 50 patients underwent PVI and EI of the LAPW with CB (EI-LAPW group). RESULTS: One-year sinus rhythm maintenance probability was significantly higher in the EI-LAPW group than in PVI-only group (80.0% vs 55.1%, P = 0.01). The success rate of constructing an LA roof block line (LA-RB), bottom block line, and EI of the LAPW was 92%, 60%, and 58%, respectively. The nadir CB temperature (-45°C ± 4°C vs -39°C ± 5°C, P = 0.005) and anatomical angle of the left atrial roof (106°C ± 30°C vs 144°C ± 17°C, P < 0.001) significantly predicted the successful LA-RB construction. The left ventricular ejection fraction was significantly higher in unsuccessful cases than in successful cases of an EI of the LAPW (64% ± 8% vs 58% ± 11%, P = 0.041). Even though the EI of the LAPW was unsuccessful, CB freezing in LAPW significantly debulked the nonscar area (≥0.1 mV) in LAPW (18.1 ± 5.6 vs 2.2 ± 3.1 cm 2 , P < 0.001) and provided the equivalent 1-year outcome of successful cases (79.3% vs 81.0%, P = 0.90). CONCLUSION: The combination of PVI and EI of the LAPW with CB provided better clinical outcomes than conventional PVI procedure for patients with PersAF.

Clinical investigation of esophageal injury from cryoballoon ablation of persistent atrial fibrillation.

BACKGROUND: The cryoballoon (CB) can be utilized for extra pulmonary vein (PV) ablation such as for a left atrial (LA) posterior wall (LAPW) isolation. However, scrutiny of the esophageal injuries during the LAPW isolation has never been performed. We sought to thoroughly investigate the esophageal lesions (ELs) and gastric hypomotility (GH) caused by an LAPW isolation using a CB. METHODS: A total of 101 persistent atrial fibrillation patients who underwent an LAPW isolation using a CB were enrolled. The CB was applied on the roof and bottom area of the LAPW after a PV isolation. The luminal esophageal temperature (LET) was monitored by a thermistor probe during the CB applications. When the LET reached 15°C, the freezing application was prematurely interrupted. Esophagogastroscopy was performed on the next day following the ablation. RESULTS: All PVs were successfully isolated in all patients. A successful LAPW isolation solely with CB ablation was performed in 72 (71.3%) patients. Cryofreezing applications were prematurely interrupted due to low LETs in 49 (48.5%) patients predominantly during the LA bottom line ablation. ELs and GH were observed in 11 (10.9%) and 16 patients (15.8%), respectively. The nadir LET tended to be lower in patients with ELs and GH than in those without (ELs: 14.8 ± 4.5°C vs 17.4 ± 6.0°C, P = 0.17; GH: 15.5 ± 4.5°C vs 17.5 ± 6.1°C, P = 0.23, respectively). CONCLUSIONS: Esophageal complications such as ELs and GH occur during the LAPW isolation with a CB. There was no reliable predictor of those adverse events.

"Clinical Impact of the Cryoballoon Temperature and Occlusion Status on the Success of Pulmonary Vein Isolation".

BACKGROUND: Complete occlusion of the pulmonary veins (PVs) with the cryoballoon (CB) is considered to be the crucial factor for a successful PV isolation (PVI). We investigated whether a complete occlusion was indispensable for a successful CB based PVI of every PV. METHODS AND RESULTS: Atrial fibrillation patients (n=123, 97; paroxysmal) undergoing a de novo PVI were enrolled. A total of 477 PVs were analyzed. The occlusion grade (OG) was scored as follows: OG3 (complete occlusion), OG2 (incomplete occlusion with slight leakage), OG1 (poor occlusion with massive leakage). There was no significant difference in the CB temperature (CBT) at all measured time points (from 30 to 120sec after freezing) and nadir CBT between OG2 and OG3 in all PVs except for the right inferior PV (RIPV). The RIPV isolation success rate was significantly lower for the OG2 status than OG3 (97.5 vs. 57.6%; p<0.0001). In contrast, there was not significant difference in the isolation success rate of the other three PVs between OG2 and OG3. In particular, the success rate of the right superior PV (RSPV) isolation was >95% for both OG2 and OG3. Phrenic nerve paralysis (PNP) was provoked during the RSPV isolation in two patients in whom the RSPVs were frozen during OG3. CONCLUSION: An OG3 may not always be required for a successful PVI of all PVs except the RIPV. OG2 could have comparable effects as OG3 in terms of a successful RSPV isolation. Not aiming for OG3 for the RSPV may reduce the risk of PNP.

Change in mobility function and its causes in adults with cerebral palsy by Gross Motor Function Classification System level: A cross-sectional questionnaire study.

BACKGROUND: The prognosis for mobility function by Gross Motor Function Classification System (GMFCS) level is vital as a guide to rehabilitation for people with cerebral palsy. OBJECTIVE: This study sought to investigate change in mobility function and its causes in adults with cerebral palsy by GMFCS level. METHODS: We conducted a cross-sectional questionnaire study. RESULTS: A total of 386 participants (26 y 8 m, SD 5 y 10 m) with cerebral palsy were analyzed. Participant numbers by GMFCS level were: I (53), II (139), III (74) and IV (120). The median age of participants with peak mobility function in GMFCS level III was younger than that in the other levels. 48% had experienced a decline in mobility. A Kaplan-Meier plot showed the risk of mobility decline increased in GMFCS level III; the hazard ratio was 1.97 (95% CI, 1.20-3.23) compared with level I. The frequently reported causes of mobility decline were changes in environment, and illness and injury in GMFCS level III, stiffness and deformity in level IV, and reduced physical activity in level II and III. CONCLUSIONS: Peak mobility function and mobility decline occurred at a younger age in GMFCS level III, with the cause of mobility decline differing by GMFCS level.

Clinical assessment of cryoballoon ablation in cases with atrial fibrillation and a left common pulmonary vein.

INTRODUCTION: Pulmonary vein isolation (PVI) using a cryoballoon (CB) is a useful tool for treating atrial fibrillation (AF); however, the clinical efficacy of the CB has never been fully investigated in patients with a left common pulmonary vein (LCPV). METHODS AND RESULTS: Three hundred twenty-four consecutive paroxysmal AF patients underwent PVI with a CB. Three-dimensional computed tomography was performed in all patients before the ablation. The clinical outcomes of the AF ablation between patients with (Group A) and without an LCPV (Group B) were compared. An LCPV was observed in 27 (8%) patients. There were no significant differences in the procedure time (149 ± 45 min vs. 143 ± 40 min, respectively; P = 0.42) and percentage needing touch up ablation between the 2 groups (26% vs. 20%, respectively; P = 0.45). At a mean follow-up of 454 ± 195 days, 282 of 324 (87%) patients were free from any atrial tachyarrhythmias (ATs) after a single procedure. Twenty out of 27 (74%) Group A patients and 262 of 297 (88%) Group B patients were free from ATs (15-month Kaplan-Meier event free rate estimates, 77% and 89%, respectively; P = 0.02). A multivariate analysis identified the presence of an LCPV and the left atrial diameter as reliable predictors of recurrent ATs. CONCLUSIONS: The long-term clinical outcomes of ablation of AF with the CB was worse in patients with an LCPV than in those without. The presence of an LCPV and the LA size seemed to be reliable predictors of a worse outcome.

Ultra-long acting calcium channel blockers may decrease accuracy of the acetylcholine provocation test.

BACKGROUND: When drug-induced coronary spasm provocation tests are performed, a washout period of >48h for calcium channel blockers (CCBs) is uniformly recommended. However, each CCB has a distinct half-life, and little is known about the influence of prior oral administration of CCBs on acetylcholine provocation test to evaluate coronary vasomotor reaction. METHODS AND RESULTS: We examined 245 consecutive patients with suspected vasospastic angina who had undergone acetylcholine provocation test. Of those patients, 29 patients had been on amlodipine, an ultra-long term acting CCB (group A), 34 on other CCBs (group O), and 182 patients on no CCB (group N). After CCBs had been withheld > 48h, we performed acetylcholine provocation, which resulted in 152 positive, 36 intermediate, and 57 negative reactions. We evaluated coronary artery tone calculated as follows: (luminal diameter after nitrate-baseline luminal diameter)÷(luminal diameter after nitrate)×100 (%). In group A patients, coronary artery tone was lower (A:9.1±6.9% vs. O:11.7±8.3% vs. N:12.1±8.5%, p=0.0011) and the positive rate of acetylcholine provocation test was lower than group O and group N (A:41% vs. O:68% vs. N:64%, p=0.047). Multivariate logistic analysis showed that taking amlodipine until 2days before acetylcholine provocation test was a significant inverse predictor for acetylcholine-provoked coronary spasm (odds ratio 0.327; 95% confidence interval 0.125-0.858, p=0.023). CONCLUSIONS: Residual vasodilatory effects of ultra-long acting CCB may decrease coronary artery tone and the vasoconstrictive reaction to acetylcholine suggesting that a 2-day pre-test drug holiday may not be long enough.

Comparative study of hemorrhagic and ischemic complications among anticoagulants in patients undergoing cryoballoon ablation for atrial fibrillation.

OBJECTIVE: Few data exist to evaluate the safety and efficacy of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) undergoing cryoballoon ablation (CB-A). This study is aimed to clarify the usefulness of DOACs in patients undergoing CB-A. METHODS: The patients (average age; 65.8±11.9 years old, male 69%) were stratified into one of five subsets based on the type of anticoagulation (warfarin, apixaban, dabigatran, rivaroxaban, or edoxaban), and underwent CB-A. A brain MRI was performed in all patients the day after the CB-A for AF. A total of 257 (19 on warfarin, 30 on apixaban, 66 on dabigatran, 81 on rivaroxaban, and 61 on edoxaban) patients met the inclusion criteria. RESULTS: The incidence of silent cerebral ischemic lesion was 1 (11.1%) patients on warfarin, 5 (33.3%) on apixaban, 8 (27.6%) on dabigatran, 10 (21.3%) on rivaroxaban, and 10 (29.4%) on edoxaban (p=0.17). Major ischemic events occurred in one patient (1.6%) on edoxaban and one (5.3%) on warfarin. Minor bleeding complications occurred in 1 patient (5.3%) on warfarin, 2 (6.7%) on apixaban, 1 (1.2%) on rivaroxaban, 5 (7.6%) on dabigatran, and 2 (3.3%) on edoxaban (p=0.24). Of note, major bleeding complications occurred in 2 patients (3.3%) on apixaban, 1 (1.2%) on rivaroxaban, 1 (1.5%) on dabigatran, 1 (1.6%) on edoxaban, and 2 (10.5%) on warfarin (p<0.05). CONCLUSIONS: Warfarin use significantly increased the risk of serious bleeding, in contrast, CB-A did not place the patients at an increased risk of complications under a DOAC treatment. There were no significant differences regarding preventing embolic events among the DOAC drugs.

Novel method for earlier detection of phrenic nerve injury during cryoballoon applications for electrical isolation of pulmonary veins in patients with atrial fibrillation.

BACKGROUND: Diaphragmatic electrogram recording during cryoballoon ablation (CB-A) of atrial fibrillation is commonly used to predict phrenic nerve palsy (PNP). OBJECTIVE: The purpose of this study was to investigate a novel method for predicting PNP at an earlier stage to prevent sustained PNP. METHODS: A total of 197 patients undergoing CB-A were enrolled. We attempted to detect PNP using fluoroscopic images of diaphragmatic contractions and by monitoring diaphragmatic compound motor action potentials (CMAPs) provoked by superior vena cava (SVC) and left subclavian vein (LCV) pacing during CB-A for bilateral pulmonary veins (PVs). Pacing of the SVC and LCV was performed at 2 outputs, 1 exceeding the pacing threshold by 10% (MIN) and the other at maximum output (MAX). The time from freezing to the initiation of PNP, values of the CMAP amplitude, and severity of PNP were compared for the 2 outputs. RESULTS: There was a significant difference in the time from freezing to initiation of PNP between MIN and MAX pacing (25.7 ± 5.7 vs 81.3 ± 7.4 seconds, P<.01). CMAP amplitudes also differed significantly (0.71 ± 0.39 vs 1.13 ± 0.42, P<.0001). SVC/LCV pacing with MIN output was able to detect PNP significantly earlier than MAX (27 ± 8 vs 91 ± 12 seconds, P<.01), and the time to PNP recovery was significantly shorter for the MIN output (20.2 ± 8.88 hours vs 4.8 ± 1.6 months, P<.001). CONCLUSION: Pacing the SVC and LCV with lower output detect PNP significantly earlier than maximal output pacing and leads to recovery from PNP on the order of hours postprocedure rather than months.

Ventricular Fibrillation in a Patient with Multi-Vessel Coronary Spasm Four Days after the Initiation of an Oral Beta-blocker.

We describe a case of ventricular fibrillation occurring in a patient with multi-vessel coronary spasm after the initiation of an oral beta-blocker. A 56-year-old man began to experience chest discomfort and his computed tomography revealed intermediate coronary stenoses. He was administered medications including an oral beta-blocker but suddenly collapsed while walking 4 days later. An automated external defibrillator detected ventricular fibrillation and delivered successful electrical cardioversion. An acetylcholine provocation test after stabilization of the status revealed triple-vessel coronary spasm. Beta-blockers may provoke exacerbation of coronary spasm and result in lethal arrhythmia. LEARNING POINTS: Beta-blockers which have a vasoconstrictive effect may occasionally provoke exacerbation of coronary spasm.Coronary spasm should be considered as a cause of lethal ventricular arrhythmia or cardiac arrest.

Popliteal Retrograde Approach is Effective and Safe for Superficial Femoral Artery Chronic Total Occlusion.

OBJECTIVE: Endovascular treatment (EVT) using a popliteal approach is effective for superficial femoral artery (SFA) chronic total occlusion (CTO); however, its effectiveness, safety, and consequent complications are unclear. MATERIALS AND METHODS: We studied 324 consecutive EVTs (in 187 patients) performed at three centers between April 2008 and March 2013, and selected all EVTs that included SFA CTO regions. A total of 91 EVTs (in 65 patients) were included and divided into two groups; "with popliteal approach" (WPA) and "without popliteal approach" (WOPA). RESULTS: Despite higher rates of hypertension (WPA, 88.9% vs. WOPA, 69.1%; p = 0.04) and CTO length >200 mm (55.6% vs. 28.3%, respectively; p <0.01), the primary success rate was better in the WPA group (97.2% vs. 78.2%, respectively; p <0.01); however, both total complication rate and major complication rate were not significantly different. We compared popliteal puncture using a sheath and using a microcatheter alone. There were no significant differences between sheath and microcatheter use in terms of primary success rates (95.5% vs. 100%, respectively; p = 0.61) and puncture site complications (22.7% vs. 14.2%, respectively; p = 0.53). CONCLUSION: A popliteal approach improved the primary success rate of EVT for SFA CTO.

Diagnostic utility of unenhanced computed tomography for acute aortic syndrome.

BACKGROUND: The diagnostic value of unenhanced computed tomography (CT) for diagnosing acute aortic dissection (AAD) and ruptured thoracic aortic aneurysm (TAA) remains unclear. METHODS AND RESULTS: We examined 219 consecutive patients who visited the emergency room with suspected acute aortic syndrome (AAS) because of chest or back pain and who underwent both unenhanced and contrast-enhanced 64-row multi-detector CT. The unenhanced CT findings were evaluated by the cardiologist on duty who was blind to the findings of contrast-enhanced CT. Diagnosis of AAS was confirmed in 103 patients (47%, 95 AAD and 8 ruptured TAA patients) based on evaluation of both unenhanced and contrast-enhanced CT images, which was used as the reference standard for validating the diagnostic value of the unenhanced CT findings. Sensitivity and specificity of the findings of a high-attenuation crescent, which represents hematoma in the aortic wall, were 61.2% and 99.1%, respectively. Sensitivity and specificity of linear high density in the aorta, which represents an intimal flap, were 59.2% and 96.6%, respectively. If unenhanced CT showed none of high-attenuation crescent, linear high density, internal displacement of intimal calcification, or TAA, the negative predictive value was 93.3%. CONCLUSIONS: Unenhanced CT is a good tool for ruling AAS in, but the false-negative rate of 6.7% is high for ruling AAS out because it has to be the minimum possible.

Cardiopulmonary arrest caused by coronary spasm after coronary vasodilator withdrawal during the peri-operative period of gastrectomy.

Calcium antagonists, nicorandil and long-acting nitrates are highly effective for preventing coronary spasm. The withdrawal of coronary vasodilators, especially calcium antagonists, is risky in cases of vasospastic angina. We herein present a case of cardiopulmonary arrest that occurred due to coronary spasm triggered by the discontinuation of coronary vasodilators during the peri-operative period of gastrectomy. Vasospastic angina patients who are not able to take oral coronary vasodilators in the peri-operative period should be maintained on a parenteral vasodilator until they are able to take them orally. Physicians should also be aware of the possible development of nitrate tolerance in patients on prolonged nitrate therapy.

Factors leading to failure to diagnose acute aortic dissection in the emergency room.

BACKGROUND: Acute aortic dissection (AAD) is often missed on initial assessment. PURPOSE: The aim of our study was to identify features associated with misdiagnosis of AAD. METHODS AND RESULTS: We examined a total of 109 emergency room (ER) patients who were ultimately diagnosed with AAD. Misdiagnosis of AAD was defined as failure to diagnose AAD at the end of the initial assessment in the ER, and occurred in 17 patients (16%). The alternate diagnosis consisted of acute coronary syndrome (n=10), other cardiovascular disease (n=3), abdominal disease (n=3), and cerebral infarction (n=1). In the misdiagnosed patients, walk-in mode of admission to the ER (29% vs. 10%, p=0.042) and anterior chest pain (71% vs. 41%, p=0.025) were more frequent, and widened mediastinum (25% vs. 55%, p=0.023) was less frequent than in diagnosed patients. The number of imaging studies performed per patient was also fewer in misdiagnosed patients than in diagnosed patients (0.82 ± 0.81 vs. 1.53 ± 0.52, p<0.001). However, there was no significant difference in in-hospital mortality (18% vs. 15%, p=0.520). Multivariate analysis showed that the strongest predictor of misdiagnosis was walk-in mode of admission (odds ratio 4.777; 95% confidence interval 1.267-18.007; p=0.021). CONCLUSIONS: Both diversity of symptoms and variability of the severity of symptoms, especially walk-in mode of admission lead ER physicians to miss AAD in about 1 in 6 cases of AAD. It is therefore important to keep AAD as a differential diagnosis in mind, even when patients present with mild enough symptoms that allow them to walk into the ER.

Clinical study of the electrophysiological effects of ischemic post-conditioning in patients with acute myocardial infarctions.

BACKGROUND: Ischemic "pre"-conditioning has been shown to have antiarrhythmic effects. The aim of this study was to investigate whether ischemic "post"-conditioning (post-CON) also has antiarrhythmic effects in ST-segment elevation myocardial infarction (STEMI) patients undergoing coronary angioplasty (PCI) as a clinical model of post-CON. METHODS AND RESULTS: A total of 61 patients suffering from an acute myocardial infarction (AMI) were included. The QT dispersion (QTd) was measured before each balloon inflation (BI) and after deflation (BD) during PCI. The hemodynamic parameters and electrocardiogram were also assessed during PCI. All data were analyzed using a logistic regression analysis. A total of 36 of 61 STEMI patients could be analyzed according to the protocol. The QTd shortened significantly as the BI and BD were repeated (p<0.05). Prior to the PCI, frequent premature ventricular contractions (PVCs) were observed in 5 patients, and the PVCs were remarkably suppressed or disappeared entirely as the BI and BD were repeated. Non-sustained ventricular tachycardia was observed prior to the PCI in 2 patients; this also disappeared as the BI and BD were repeated. Ventricular fibrillation (VF) occurred in 1 patient prior to PCI, necessitating D-C cardioversion. After repeating the BI and BD during PCI, VF no longer recurred. CONCLUSIONS: In the majority of the AMI patients studied, post-CON exhibited significant antiarrhythmic effects as assessed by the change in the QTd. The ventricular dysarrhythmias were also suppressed during the PCI.