Restrictive or Liberal Transfusion Strategy in Myocardial Infarction and Anemia.

BACKGROUND: A strategy of administering a transfusion only when the hemoglobin level falls below 7 or 8 g per deciliter has been widely adopted. However, patients with acute myocardial infarction may benefit from a higher hemoglobin level. METHODS: In this phase 3, interventional trial, we randomly assigned patients with myocardial infarction and a hemoglobin level of less than 10 g per deciliter to a restrictive transfusion strategy (hemoglobin cutoff for transfusion, 7 or 8 g per deciliter) or a liberal transfusion strategy (hemoglobin cutoff, <10 g per deciliter). The primary outcome was a composite of myocardial infarction or death at 30 days. RESULTS: A total of 3504 patients were included in the primary analysis. The mean (±SD) number of red-cell units that were transfused was 0.7±1.6 in the restrictive-strategy group and 2.5±2.3 in the liberal-strategy group. The mean hemoglobin level was 1.3 to 1.6 g per deciliter lower in the restrictive-strategy group than in the liberal-strategy group on days 1 to 3 after randomization. A primary-outcome event occurred in 295 of 1749 patients (16.9%) in the restrictive-strategy group and in 255 of 1755 patients (14.5%) in the liberal-strategy group (risk ratio modeled with multiple imputation for incomplete follow-up, 1.15; 95% confidence interval [CI], 0.99 to 1.34; P = 0.07). Death occurred in 9.9% of the patients with the restrictive strategy and in 8.3% of the patients with the liberal strategy (risk ratio, 1.19; 95% CI, 0.96 to 1.47); myocardial infarction occurred in 8.5% and 7.2% of the patients, respectively (risk ratio, 1.19; 95% CI, 0.94 to 1.49). CONCLUSIONS: In patients with acute myocardial infarction and anemia, a liberal transfusion strategy did not significantly reduce the risk of recurrent myocardial infarction or death at 30 days. However, potential harms of a restrictive transfusion strategy cannot be excluded. (Funded by the National Heart, Lung, and Blood Institute and others; MINT ClinicalTrials.gov number, NCT02981407.).

Demographics and risk factors that influence the prevalence of depression in patients attending cardiac rehabilitation.

Depression has been associated with adverse outcomes in patients with cardiac disease. Data on its prevalence and the factors influencing it are limited in the cardiac rehabilitation program (CRP) setting. To elucidate the prevalence of and the factors that influence depression in patients attending CRP. Patients attending the CRP from 2003 to 2016 were included in the study. All patients had a Beck Depression Inventory-II (BDI-II) performed prior to commencement in CRP and were followed longitudinally. The BDI-II for the 4989 patients were as follows: 0 to 13 (normal) = 3623 (72%); 14 to 19 (mild depression) = 982 (20%); 20 to 28 (moderate depression) = 299 (6%); 29 to 63 (severe depression) = 85 (2%). The BDI-II (mean ± SEM) for males (mean age: 60.8 ± 0.1 years) and females (mean age: 63.4 ± 0.3 years, P < .001) were 7.0 ±â€…0.1 and 8.5 ±â€…0.2 (P < .001), respectively. Elevated BDI-II scores (14-63) were more common in type 1 (41.1%) and type 2 (30.5%) diabetics than nondiabetics (25.7%). Similarly, elevated scores were more common in smokers (36.1%) than never-smokers (24.7%). The BDI-II scores for Caucasians, South Asians, and East Asians were 7.3 ±â€…0.1, 8.0 ±â€…0.3, and 7.0 ±â€…0.3 respectively (P = .01 for CA vs SA by 1-way ANOVA and least significant difference test). The prevalence of depression is high in patients attending CRP affecting 28% of the population. BDI-II is a simple validated screening tool that can be applied to patients attending CRP. Diabetics, current smokers, and South Asians all had a higher prevalence of depression.

Differences in Clinical Measures and Outcomes in South Asians vs Caucasians Attending Cardiac Rehabilitation.

BACKGROUND: South Asians have a greater predisposition to cardiac events, compared to Caucasians. Although cardiac rehabilitation programs (CRPs) are known to improve outcomes, data are sparse regarding benefits acquired by South Asians vs Caucasians. The objective of the current study was to determine the outcomes of South Asian patients undergoing CRPs, compared to Caucasian patients. METHODS: This study compared baseline characteristics and outcomes in all patients attending a CRP in Edmonton, Canada with a proportionately large South Asian population. RESULTS: From 1998 to 2016, a total of 811 South Asians and 5406 Caucasians attended CRPs. Baseline characteristics revealed that there were more nonsmokers (73.4% vs 29.4%, P < 0.001), with a lower body mass index (26.8 ± 0.1 vs 29.6 ± 0.1, P < 0.001), but higher prevalence of diabetes (37.7% vs 20.5%, P < 0.001) in the South Asian population. Outcome measures revealed that South Asians spent less time in the CRP (6.9 weeks ± 0.1 vs 7.3 weeks ± 0.1, P < 0.001), attended the nutrition class less (36.2% vs 53.4%, P < 0.001), and had a lower 6-minute walk improvement (66.9 m vs 73.6 m, P < 0.001). Frequency of use of ß-blockers (86.9% vs 86.1%, P > 0.05), antiplatelet agents (96.3% vs 97.1%, P > 0.05), angiotensin-converting enzyme inhibitors (79.9% vs 80.0%, P > 0.05), and cholesterol-lowering agents (91.4% vs 93.8%, P > 0.05) was not significantly different. CONCLUSIONS: Although South Asians seem to be prescribed and use proven pharmacologic treatments to the same extent as Caucasians, they appeared to benefit less from CRPs. Given higher event rates in South Asians, consideration should be given to altering the delivery of CRPs to South Asians to improve their efficacy.

CONTEXTE: Les Asiatiques du Sud sont davantage prédisposés aux événements cardiaques que les Caucasiens. Si l'on sait que les programmes de réadaptation cardiaque (PRC) permettent d'améliorer les résultats, rares sont cependant les données sur les effets bénéfiques des PRC chez les Asiatiques du Sud comparativement aux Caucasiens. L'objectif de la présente étude était de comparer les résultats obtenus par les patients sud-asiatiques ayant suivi un PRC à ceux des patients caucasiens. MÉTHODOLOGIE: Dans cette étude, nous avons comparé les caractéristiques initiales et les résultats de tous les patients ayant suivi un PRC à Edmonton, au Canada, qui compte une population sud-asiatique proportionnellement importante. RÉSULTATS: Entre 1998 et 2016, 811 patients sud-asiatiques et 5406 patients caucasiens ont suivi des PRC. L'examen des caractéristiques initiales montre que les patients sud-asiatiques étaient plus souvent des non-fumeurs (73,4 % vs 29,4 %, p < 0,001) et présentaient un indice de masse corporelle inférieur (26,8 ± 0,1 vs 29,6 ± 0,1, p < 0,001), mais une prévalence du diabète plus élevée (37,7 % vs 20,5 %, p < 0,001) que les patients caucasiens. Les mesures des résultats ont révélé que les patients sud-asiatiques avaient consacré moins de temps au PRC (6,9 semaines ± 0,1 vs 7,3 semaines ± 0,1, p < 0,001), avaient moins assisté au cours sur la nutrition (36,2 % vs 53,4 %, p < 0,001), et avaient obtenu une amélioration plus faible de leur résultat au test de marche de 6 minutes (66,9 m vs 73,6 m, p < 0,001). Aucune différence significative entre les deux groupes n'a été observée en ce qui concerne la fréquence d'utilisation des bêtabloquants (86,9 % vs 86,1 %, p > 0,05), des agents antiplaquettaires (96,3 % vs 97,1 %, p > 0,05), des inhibiteurs de l'enzyme de conversion de l'angiotensine (79,9 % vs 80,0 %, p > 0,05) et des hypocholestérolémiants (91,4 % vs 93,8 %, p > 0,05). CONCLUSIONS: Si les Asiatiques du Sud se voient prescrire et utiliser des traitements pharmacologiques éprouvés dans la même mesure que les Caucasiens, ils semblent cependant retirer moins d'effets bénéfiques des PRC que ces derniers. Compte tenu de la fréquence plus élevée des événements cardiaques dans la population sud-asiatique, il y aurait lieu d'envisager la possibilité de modifier les modalités d'administration de ces programmes pour les personnes de ce groupe afin d'améliorer leur efficacité.

Screening for Fabry Disease in patients with unexplained left ventricular hypertrophy.

Fabry Disease (FD) is a systemic disorder that can result in cardiovascular, renal, and neurovascular disease leading to reduced life expectancy. FD should be considered in the differential of all patients with unexplained left ventricular hypertrophy (LVH). We therefore performed a prospective screening study in Edmonton and Hong Kong using Dried Blood Spot (DBS) testing on patients with undiagnosed LVH. Participants found to have unexplained LVH on echocardiography were invited to participate and subsequently subjected to DBS testing. DBS testing was used to measure α-galactosidase (α-GAL) enzyme activity and for mutation analysis of the α-galactosidase (GLA) gene, both of which are required to make a diagnosis of FD. DBS testing was performed as a screening tool on patients (n = 266) in Edmonton and Hong Kong, allowing for detection of five patients with FD (2% prevalence of FD) and one patient with hydroxychloroquine-induced phenocopy. Left ventricular mass index (LVMI) by GLA genotype showed a higher LVMI in patients with IVS4 + 919G > A mutations compared to those without the mutation. Two patients were initiated on ERT and hydroxychloroquine was discontinued in the patient with a phenocopy of FD. Overall, we detected FD in 2% of our screening cohort using DBS testing as an effective and easy to administer screening tool in patients with unexplained LVH. Utilizing DBS testing to screen for FD in patients with otherwise undiagnosed LVH is clinically important due to the availability of effective therapies and the value of cascade screening in extended families.

Safety and efficacy of AAIR pacing in selected patients with sick sinus syndrome.

BACKGROUND: The DANPACE study suggested implanting dual-pacing dual-sensing dual-response rate-adaptive (DDDR) pacemakers in patients with sick sinus syndrome, even though 90.7% of their atrial-pacing atrial-sensing inhibited-response rate-adaptive (AAIR) group did not require upgrade. Most centers implant DDDR pacemakers due to risk of future atrioventricular (AV) block. Given that AAIR pacemakers are less expensive, have one less lead with potentially one less point of complication, we question whether DDDR pacemakers are superior to AAIR pacemakers. We aim to describe long-term outcomes of AAIR implants. METHODS: Patients presenting to the Grey Nuns Hospital in Edmonton, Canada from 1990 to 2012 with sick sinus syndrome without AV block had AAIR pacemakers implanted. Outcomes that were measured over the follow-up time included need for ventricular lead reoperation, incidence of AV block and incidence of sudden cardiac death from AV block. RESULTS: During this period, 330 patients presented with sick sinus syndrome. Eighty-seven (26.4%) patients met criteria for and received AAIR pacemakers. Seventy-eight (91.8%) did not require upgrade over mean follow-up of 10.6 ±â€Š0.6 years. Amongst this group, 31 patients (39.7%) were alive, whereas 47 (60.3%) were deceased at end of follow-up due to other comorbidities. No sudden deaths were attributable to AV block. Only 7 patients (8.2%) required ventricular lead reoperation: 2 (2.4%) presented urgently with symptomatic AV block; 3 (3.5%) had atrial fibrillation requiring beta-blockade; 1 (1.2%) had atrial lead dislodgment; and 1 (1.2%) was electively upgraded at battery end-of-life. CONCLUSIONS: This study looks at safety of AAIR pacemakers with only 2.4% of patients developing AV block requiring urgent upgrade. Approximately 91.8% of patients remained with their original AAIR pacemakers (mean follow-up 10.6 vs 5.4 years in DANPACE). Our findings are similar to the DANPACE study but our conclusions are different as we believe AAIR pacing should be considered for selected patients with sick sinus syndrome without AV block.

Effect of Cardiac Rehabilitation on South Asian Individuals With Cardiovascular Disease: Results From the APPROACH Registry.

BACKGROUND: Unequivocally, cardiac rehabilitation (CR) in patients with established cardiovascular disease improves survival. However, its effect on higher-risk ethnic groups has not been explored. Accordingly, we evaluated the effect of CR on South Asian (SA) compared with European Canadians with coronary artery disease (CAD). METHODS: Using the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) registry, 26,167 patients from Edmonton, Alberta who received coronary angiography with documented CAD were reviewed (January 2002 to March 2012). After excluding Chinese patients, 1027 SA patients were compared with 11,992 European Canadian patients using validated surname algorithms. Adjustment was performed using a Cox proportional hazard model. RESULTS: Of the SA cohort, 50.6% attended CR, compared with 43.0% of the European Canadian cohort (P < 0.001). After adjustment, CR was associated with long-term survival irrespective of ethnic group (total study population: hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.52-0.63; P < 0.001; SA population: HR, 0.63; 95% CI, 0.40-0.99; P = 0.045; European population: HR, 0.57; 95% CI, 0.52-0.63; P < 0.001). When comparing SA vs European Canadians attending CR, improved survival was observed in SA patients (HR, 0.58; 95% CI, 0.40-0.85; P < 0.001). This benefit appeared limited to SA patients who completed CR (complete CR: HR, 0.37; 95% CI, 0.17-0.85; P = 0.02; incomplete CR: HR, 0.78; 95% CI, 0.45-1.35; P = 0.38). CONCLUSIONS: Overall, referral rates to CR remains low but attendance appears higher in SA patients. Among those who attended CR, there is a strong association with improved survival irrespective of ethnic status. In SA patients with CAD, attendance and completion of CR should be strongly endorsed because of its incremental benefit.

Practice patterns and clinical outcomes among non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients presenting to primary and tertiary hospitals: insights from the EARLY glycoprotein IIb/IIIa inhibition in NSTE-ACS (EARLY-ACS) trial.

OBJECTIVES: We evaluated patients at tertiary [both percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) capable] and primary hospitals in the EARLY-ACS trial. BACKGROUND: Early invasive management is recommended for high-risk non-ST-segment elevation acute coronary syndromes. METHODS: We evaluated outcomes in 9,204 patients presenting to: tertiary sites, primary sites with transfer to tertiary sites ("transferred") and those who remained at primary sites ("non-transfer"). RESULTS: There were 348 tertiary (n = 7,455 patients) and 89 primary hospitals [n = 1,749 patients (729 transferred; 1,020 non-transfer)]. Significant delays occurred in time from symptom onset to angiography (49 hr), PCI (53h), and CABG (178 hr) for transferred patients (P < 0.001). Non-transfer patients had less 30-day death/myocardial infarction [9.4% vs. 11.7% (tertiary); adjusted odds ratio (OR): 0.78 (0.62-0.97), P = 0.026]; transferred (14.0%) and tertiary patients were similar [adjusted OR: 1.23 (0.98-1.53), P = 0.074]. Non-transfer patients had lower 1-year mortality [4.3% vs. 6.3% (tertiary); adjusted hazard ratio (HR): 0.64 (0.47-0.87), P = 0.005]: there was no difference between transferred and tertiary patients [5.2% vs. 6.3%; adjusted HR: 0.80 (0.58-1.12), P = 0.202]. Despite similar rates of catheterization, GUSTO severe/moderate bleeding within 120 hr was less in non-transfer [3.1% vs. 6.7% (tertiary); adjusted OR: 0.47 (0.32-0.68), P < 0.001], whereas transferred (6.1%) and tertiary patients were similar [adjusted OR: 0.94 (0.68-1.30), P = 0.693]. There was no difference in non-CABG bleeding. CONCLUSIONS: Timely angiography and revascularization were often not achieved in transferred patients. Non-transferred patients presenting to primary sites had the lowest event rates and the best long-term survival.

A 19-year study on pacemaker-related infections: a claim for using postoperative antibiotics.

BACKGROUND: Although the incidence of pacemaker-related infection (PMINF) is low, it necessitates removal of the pacing system. There is currently no consensus on antibiotics during implantation. METHODS: A prospective database on patients undergoing pacemaker surgery from 1991 to 2009 was reviewed to determine factors associated with PMINF. Specifically, three eras of antibiotic use were compared to elucidate the effect of antibiotics on PMINF: no antibiotics, perioperative antibiotics, and peri- plus postoperative antibiotics. RESULTS: There were 3,253 procedures with PMINF identified in 46 (1.4%) patients. Over 19 years, PMINF incidence fell from 3.6% (no antibiotics) to 2.9% (perioperative antibiotics), to 0.4% (peri- plus postoperative antibiotics). On univariate analysis, the following were associated with PMINF: nonuse of postoperative antibiotics (3.0% vs 0.4%, P < 0.001), year of implant (P < 0.001), repeat procedures (2.3% vs 1%, P = 0.006), nonuse of perioperative antibiotics (3.6% vs 1.3%, P = 0.027). With postoperative antibiotics, rates were significantly reduced in new implants (1/1,289 = 0.1% vs 22/967 = 2.3%, P < 0.001) and repeat procedures (7/692 = 1.0% vs 16/305 = 5.2%, P < 0.001). On multivariate analysis, the following were significant (standardized coefficients denote relative importance): postoperative antibiotics (0.776), repeat procedures (0.508), year of implant (0.142), perioperative antibiotics (0.088). CONCLUSIONS: The PMINF rate is reduced significantly by perioperative antibiotics with a further significant reduction with postoperative antibiotics. However, the reduction in PMINF rate could be a result of changes in practice in the different time eras. This study suggests consideration of perioperative followed by postoperative antibiotics to minimize pacemaker infections.

Evidence for cholesterol hyperabsorbers and hyperproducers based on comparative low-density lipoprotein reductions achieved by ezetimibe versus statins.

PURPOSE: To investigate the hypothesis that some patients are hyperproducers of cholesterol while others are hyperabsorbers by comparing the low-density lipoprotein (LDL) responses to statins versus ezetimibe adjunct therapy. METHODS: Consecutive patients (N = 109), who received statin monotherapy followed by ezetimibe adjunct therapy, were prospectively studied. The expected LDL levels for each patient on statin and on ezetimibe adjunct therapy were calculated. The difference between expected and actual LDL levels on statin and on ezetimibe adjunct therapy was calculated for each patient and subsequently correlated. RESULTS: The mean LDL levels (mg/dL) were baseline, 168.7 ± 3.6; on statin, 104.2 ± 2.6; on ezetimibe adjunct, 74.2 ± 2.2. Statins reduced LDL by 36.7 ± 1.5%, while adding ezetimibe resulted in a further reduction of 28.1 ± 1.4%. The percent LDL reduction by statin was negatively correlated to the percent reduction by ezetimibe adjunct therapy (r = -0.29, P = .002). The difference between expected and actual LDL levels on statin was negatively correlated to that on ezetimibe adjunct therapy (r = -0.38, P < .001). CONCLUSIONS: This study demonstrated that the LDL response to ezetimibe is inversely related to the response to statin. This lends support to the hypothesis that some patients may be hyperabsorbers of cholesterol while others may be hyperproducers. This suggests that a less than expected response to the initial dose of statin in a patient would likely require the addition of ezetimibe to achieve the recommended target levels in spite of the use of maximum dose statin therapy.

Impact of AV conduction disorders on SafeR mode performance.

PURPOSE: CAN-SAVE R is a Canadian multicenter study that compares the effects of a new pacing mode algorithm designed to minimize right ventricular (V) pacing versus DDD mode with a long atrioventricular (AV) delay in a general population of pacemaker (PM) recipients. STUDY PARTICIPANTS: Patients with permanent atrial fibrillation (AF) or high-degree AV block (AVB) were excluded. We present preliminary data collected in 208 patients (mean age=71 +/- 11 years, 68% men), for the 2-month baseline period during which all PM were programmed in the new pacing mode. The pacing indications were sinus node disease (SND) without AVB in 39%, AVB without SND in 30%, SND and AVB in 16%, and miscellaneous in 15% of patients. RESULTS: The mean percent V pacing in the overall population was 9.5 +/- 23.8% (range=0-100%, median <1%), ranging between 0.5 +/- 1.5% (median=0) in patients without AVB and 18.7 +/- 31.2% in patients (median = 1) with AVB. Adverse events potentially related to the new pacing mode were observed in two patients with AVB. CONCLUSIONS: A new pacing mode was effective and safe in a general population of PM recipients without permanent AVB and was associated with an overall <1% median V pacing. CAN-SAVE R will compare the long-term effects of the new pacing mode with DDD with a long AV delay on clinical outcomes and cardiac function.

Pacemaker longevity: are we getting what we are promised?

BACKGROUND: Although pacemaker manufacturers provide projections on longevity, these projections cannot be relied upon due to the assumptions of output parameters being far in excess of those programmed in clinical practice. OBJECTIVE: The purpose of this review was to compare the actual longevity to the calculated longevity of pacemakers based on battery cell characteristics taking into account individual programmed parameters, mode, degree of usage, and percent pacing. This was also compared to the manufacturers' own projected longevities. METHODS: Patients who had a pacemaker replaced between 1998 and 2003 were included (n = 124). Cell characteristics were obtained from manufacturers and programmed parameters were obtained at each visit. Stepwise calculations were done for each visit to find current drain during each interval, and then were used in a weighted average to find the total average lifetime current drain. This was subsequently used to find a calculated longevity for each pacemaker to be compared to the actual longevity observed. RESULTS: The pacemakers lasted 491+/-92 days (mean+/-SEM) less than calculated. There was also a difference between dual- and single-chamber devices (though not statistically significant). Moreover, it was found that there were significant differences between manufacturers. CONCLUSIONS: There appears to be a significant discrepancy between calculated and actual longevities, confirming that battery depletion occurs earlier than expected. This suggests that current drain expended for ancillary functions may be considerable. Another factor may be pre-implantation drain. Vigilance with programming of outputs, modes, sensors, heart rates, and ancillary functions could potentially extend longevity and postpone/obviate the need for costly repeat surgery with its attended risk of complications. Furthermore, the differences between manufacturers seem to parallel the clinical impressions.

Right precordial leads and lead aVR at exercise electrocardiography: does it change test results?

BACKGROUND: A recent study on exercise testing (ET) suggested that ST-segment changes in the right precordial leads (RPL) may increase its sensitivity substantially. However, this study looked at a highly selected population of patients who all underwent thallium-201 scintigraphy and coronary angiography. The present study evaluated the clinical utility of ST-segment changes in the RPL and lead aVR in an unselected population of patients undergoing ET. METHODS: A total of 906 consecutive patients who received ET were included in the study. ET was done using the Bruce Protocol with a 12-lead electrocardiogram (ECG) substituting V(4)R and V(6)R for V(1) and V(6). Leads V(1) and V(6) were selected for omission as these two leads hardly ever manifest changes in isolation. Substituting two leads would obviate the need for a more complex recording system, thus improving clinical utility. RESULTS: On the basis of horizontal/downsloping ST-segment depression (STD) of 1.0 mm or more (the usually accepted criterion for a positive ET), 159 (17.5%) patients had a positive ET. In those patients with a negative ET (545 patients), 4 patients (0.7%) manifested STD and 5 patients (0.9%) manifested ST-segment elevation (STE) in leads V(4)R and/or V(6)R, respectively. Of note, 44.7% of the positive ET group had STE in lead aVR. CONCLUSION: The use of ST-segment changes in RPL during exercise stress testing does not appreciably change the test results of a standard ET. If one was to consider an additional marker, STE in aVR may be more useful, as it shows a stronger correlation with positive tests and does not require the recording of additional leads.

Is the outcomes of early ST-segment resolution after thrombolytic therapy in acute myocardial infarction always favorable?

AIMS: To determine whether the magnitude of ST-segment resolution after thrombolytic therapy (TT) predicts short- and long-term outcomes in an unselected population of patients with an acute myocardial infarction (AMI). BACKGROUND: Recent studies suggest that resolution of ST-segment elevation (STE) on the 2-hour post-TT electrocardiogram (ECG) is a useful predictor of prognosis. However, these studies were restricted to clinical trials where only 15% to 20% of the patients receiving TT were often enrolled. METHODS: The present study evaluated an unselected consecutive group of patients who received TT. All clinical, investigational, and follow-up data had been collected in a prospective manner. The analysis of ECGs was done retrospectively with the reader blinded to the clinical course. STE at 80 milliseconds after the J point was measured on the baseline and 90-minute ECG using a hand-held caliper. The resolution of STE was categorized as complete (>or=70%), partial (30% to <70%), and none (<30%) as has been done in previous studies. RESULTS: Three hundred fifty-two patients (250 men, 102 women; age, mean+/-SEM, 61.8+/-1.0 years; peak creatine kinase, 1938+/-185 micromol/L; door to needle time, 50.0+/-6 minutes, <30 minutes, 50%; <45 minutes, 70%) with AMIs who received TT were included in the study. Inhospital deaths and recurrent AMI/postinfarct angina revealed no significant association with increasing ST-segment resolution (P>.05). A 70% or higher ST-segment resolution was associated with a significantly lower incidence of inhospital congestive heart failure (CHF) and CHF/death (P<.05). Similarly, with a 70% or higher ST-segment resolution, there was a lower incidence in the 1-year outcomes of CHF and death/CHF. However the 1-year occurrences of unstable angina or recurrent AMIs taken singly did not bear a correlation to increasing magnitudes of ST-segment resolution (P>.05). Although as a composite measure, there was an increasing trend with ST-segment resolution. CONCLUSIONS: Magnitude of ST-segment resolution after TT appears to demonstrate a dichotomous relationship to measured outcomes. Although there is a lower incidence of death/CHF with increasing ST-segment resolution, there appears to be a higher likelihood for recurrent AMI/unstable angina.

Evaluation of the appropriateness of pacemaker mode selection in bradycardia pacing: how closely are the ACC/AHA guidelines followed?

Although guidelines for selection of the appropriate pacing mode have been published, little data is available on how closely these are followed in the clinical setting. All 738 patients (men 412, women 326; age 73.4 +/- 0.46 years; range 19-101 years) who underwent pacemaker implantation from 1996 to 2000 were reviewed to determine if the appropriate mode was selected based on the ACC/AHA guidelines with the data collected prospectively. Demographic, investigational, and implantation data including the presence of sinus disease and/or atrioventricular block, diagnosis, indication for pacing, ACC/AHA class indication for device therapy, recommended ACC/AHA mode, implanted mode, and reason for not using the recommended mode were entered into an SPSS data base. Of 738 patients, 708 were cross-tabulated for a match to the guidelines of which 358 (50.6%) had a mode selected that did not conform. The reasons were advanced physical disability (16%), physician choice without identifiable reason (21%), rate modulation selected without identifiable indication (16%), DDD implanted instead of VDD (25%), advanced age (9%), rare need for pacing (6%), a need for specific device features (5%), and unstable stimulation thresholds or difficult venous access (2%). In the treatment of bradyarrhythmias, deviation from the ACC/AHA indicated mode occurred in a substantial proportion of pacing system implantations. However, in many, the deviation appeared appropriate considering the patient's clinical status. Nevertheless, in a smaller proportion of patients the deviation appeared inappropriate requiring rectification. The two outstanding categories were: (1) elderly denied a dual chamber system with no clinical explanation and (2) selection of rate-modulated devices without any indication of chronotropic incompetence.

Clinical utility of ST-segment depression in lead AVR in acute myocardial infarction.

The present study evaluated the prevalence and significance of ST-segment depression (STD) in lead aVR on the admission 12-lead electrocardiogram in 307 consecutive patients with an acute myocardial infarction (AMI) with ST-segment elevation. STD in aVR was present in a significantly higher proportion of patients with inferior/posterior AMIs. Within inferior/posterior AMIs those with STD in aVR had significantly more concomitant STD in V(1), V(2), V(3) and more concomitant STesegment elevation in V(5), V(6) and right precordial leads. These data suggests that STD in aVR may point to a coronary artery with a large area of supply as the culprit vessel responsible for the AMI.

Postpacemaker implant pericarditis: incidence and outcomes with active-fixation leads.

Pericarditis has been noted as a potential complication of pacemaker implantation. This study evaluated the risk of developing pericarditis following pacemaker implantation with active-fixation atrial leads. Included were 1,021 consecutive patients (mean age 73.4+/-0.4 years, range 16-101 years; 45.2% women) undergoing new pacemaker system implantation between 1991 and 1999 who were reviewed for the complication of pericarditis. The incidence and outcomes of postimplantation pericarditis in patients receiving active-fixation atrial leads were compared to those not receiving these leads. Of 79 patients who received active-fixation atrial leads, 4 (5%) developed pericarditis postpacemaker implantation. Of 942 patients with passive-fixation atrial leads or no atrial lead (i.e., a ventricular lead only), none developed pericarditis postoperatively (P < 0.001). Of patients receiving active-fixation ventricular leads only (n = 97), none developed pericarditis. No complications were apparent at the time of implantation in patients who developed pericarditis. Pleuritic chest pain developed between 1 and 28 hours postoperatively. Three patients had pericardial rubs without clinical or echocardiographic evidence of tamponade. They were treated conservatively with acetylsalicylic acid or ibuprofen and their symptoms resolved without sequelae in 1-8 days. One patient (without pericardial rub) died due to cardiac tamponade on postoperative day 6. Postmortem examination revealed hemorrhagic pericarditis with no gross evidence of lead perforation. Pericarditis complicates pacemaker implantation in significantly more patients who receive active-fixation atrial leads. It may be precipitated byperforation of the atrial lead screw through the thin atrial wall. Patients developing postoperative pericarditis should befollowed closely due to the risk of cardiac tamponade.