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Gervasio A Lamas

Publications and source records attributed to Gervasio A Lamas.

At least 19 recordsLinked to original sources
PubMed2006

Characterization of health-related quality of life in heart failure patients with preserved versus low ejection fraction in CHARM.

BACKGROUND: Limited comparative studies assessing the health-related quality of life (HRQL) in heart failure (HF) patients with preserved vs. low ejection fraction (LVEF) have been disparate. AIMS: The aims of this study were a) to characterize HRQL in a large population of HF patients with preserved and low LVEF and b) to determine the factors associated with worse HRQL. METHODS: Patients with symptomatic HF (NYHA Class II-IV) enrolled in the Candesartan in Heart Failure: Assessment of Reduction in Mortality and Morbidity (CHARM) HRQL study completed the Minnesota Living with Heart Failure questionnaire at randomization. Patients were stratified into 2 HF cohorts: preserved LVEF (>40%) and low LVEF (<or=40%). RESULTS: In 2709 of the eligible 2744 (98.6%) patients, the summary scores ranged from 0 to 105 (mean 40.9). There were no differences in overall responses of HF patients with preserved vs. low LVEF (41.1 vs. 40.8). Independent factors associated with worse HRQL in both populations included female gender, younger age, higher body mass index, lower systolic blood pressure, greater symptom burden, and worse functional status. CONCLUSIONS: In symptomatic HF patients, HRQL is equally impaired in both preserved and low LVEF populations. Targeting improvement in symptoms and HRQL is an important treatment objective in all HF patients.

Adult↗
PubMed2006

Coronary intervention for persistent occlusion after myocardial infarction.

BACKGROUND: It is unclear whether stable, high-risk patients with persistent total occlusion of the infarct-related coronary artery identified after the currently accepted period for myocardial salvage has passed should undergo percutaneous coronary intervention (PCI) in addition to receiving optimal medical therapy to reduce the risk of subsequent events. METHODS: We conducted a randomized study involving 2166 stable patients who had total occlusion of the infarct-related artery 3 to 28 days after myocardial infarction and who met a high-risk criterion (an ejection fraction of <50% or proximal occlusion). Of these patients, 1082 were assigned to routine PCI and stenting with optimal medical therapy, and 1084 were assigned to optimal medical therapy alone. The primary end point was a composite of death, myocardial reinfarction, or New York Heart Association (NYHA) class IV heart failure. RESULTS: The 4-year cumulative primary event rate was 17.2% in the PCI group and 15.6% in the medical therapy group (hazard ratio for death, reinfarction, or heart failure in the PCI group as compared with the medical therapy group, 1.16; 95% confidence interval [CI], 0.92 to 1.45; P=0.20). Rates of myocardial reinfarction (fatal and nonfatal) were 7.0% and 5.3% in the two groups, respectively (hazard ratio, 1.36; 95% CI, 0.92 to 2.00; P=0.13). Rates of nonfatal reinfarction were 6.9% and 5.0%, respectively (hazard ratio, 1.44; 95% CI, 0.96 to 2.16; P=0.08); only six reinfarctions (0.6%) were related to assigned PCI procedures. Rates of NYHA class IV heart failure (4.4% vs. 4.5%) and death (9.1% vs. 9.4%) were similar. There was no interaction between treatment effect and any subgroup variable (age, sex, race or ethnic group, infarct-related artery, ejection fraction, diabetes, Killip class, and the time from myocardial infarction to randomization). CONCLUSIONS: PCI did not reduce the occurrence of death, reinfarction, or heart failure, and there was a trend toward excess reinfarction during 4 years of follow-up in stable patients with occlusion of the infarct-related artery 3 to 28 days after myocardial infarction. (ClinicalTrials.gov number, NCT00004562 [ClinicalTrials.gov].).

Aged↗
PubMed2006

Randomized trial of percutaneous coronary intervention for subacute infarct-related coronary artery occlusion to achieve long-term patency and improve ventricular function: the Total Occlusion Study of Canada (TOSCA)-2 trial.

BACKGROUND: In the present study, we sought to determine whether opening a persistently occluded infarct-related artery (IRA) by percutaneous coronary intervention (PCI) in patients beyond the acute phase of myocardial infarction (MI) improves patency and indices of left ventricular (LV) size and function. METHODS AND RESULTS: Between May 2000 and July 2005, 381 patients with an occluded native IRA 3 to 28 days after MI (median 10 days) were randomized to PCI with stenting (PCI) or optimal medical therapy alone. Repeat coronary and LV angiography was performed 1 year after randomization (n=332, 87%). Coprimary end points were IRA patency and change in LV ejection fraction. Secondary end points included change in LV end-systolic and end-diastolic volume indices and wall motion. PCI was successful in 92%. At 1 year, 83% of PCI versus 25% of medical therapy-only patients had a patent IRA (P<0.001). LV ejection fraction increased significantly (P<0.001) in both groups, with no between-group difference: PCI 4.2+/-8.9 (n=150) versus medical therapy 3.5+/-8.2 (n=136; P=0.47). Median change (interquartile range) in LV end-systolic volume index was -0.5 (-9.3 to 5.0) versus 1.0 (-5.7 to 7.3) mL/m2 (P=0.10), whereas median change (interquartile range) in LV end-diastolic volume index was 3.2 (-8.2 to 13.3) versus 5.3 (-4.6 to 23.2) mL/m2 (P=0.07) in the PCI (n=86) and medical therapy-only (n=76) groups, respectively. CONCLUSIONS: PCI with stenting of a persistently occluded IRA in the subacute phase after MI effectively maintains long-term patency but has no effect on LV ejection fraction. On the basis of these findings and the lack of clinical benefit in the main Occluded Artery Trial, routine PCI is not recommended for stable patients with a persistently occluded IRA after MI.

Adult↗
PubMed2006

Cardiovascular outcomes with atrial-based pacing compared with ventricular pacing: meta-analysis of randomized trials, using individual patient data.

BACKGROUND: Several randomized trials have compared atrial-based (dual-chamber or atrial) pacing with ventricular pacing in patients with bradycardia. No trial has shown a mortality reduction, and only 1 small trial suggested a reduction in stroke. The goal of this review was to determine whether atrial-based pacing prevents major cardiovascular events. METHODS AND RESULTS: A systematic review was performed of publications since 1980. For inclusion, trials had to compare an atrial-based with a ventricular-based pacing mode; use a randomized, controlled, parallel design; and have data on mortality, stroke, heart failure, or atrial fibrillation. Individual patient data were obtained from 5 of the 8 identified studies, representing 95% of patients in the 8 trials, and a total of 35 000 patient-years of follow-up. There was no significant heterogeneity among the results of the individual trials. There was no significant reduction in mortality (hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.87 to 1.03; P=0.19) or heart failure (HR, 0.89; 95% CI, 0.77 to 1.03; P=0.15) with atrial-based pacing. There was a significant reduction in atrial fibrillation (HR, 0.80; 95% CI, 0.72 to 0.89; P=0.00003) and a reduction in stroke that was of borderline significance (HR, 0.81; 95% CI, 0.67 to 0.99; P=0.035). There was no convincing evidence that any patient subgroup received special benefit from atrial-based pacing. CONCLUSIONS: Compared with ventricular pacing, the use of atrial-based pacing does not improve survival or reduce heart failure or cardiovascular death. However, atrial-based pacing reduces the incidence of atrial fibrillation and may modestly reduce stroke.

Arrhythmias, Cardiac↗
PubMed2006

Treatment crossovers did not affect randomized treatment comparisons in the Mode Selection Trial (MOST).

OBJECTIVES: We evaluated the impact of treatment crossovers on study results in the Mode Selection Trial (MOST). BACKGROUND: The MOST study, a 2,010-patient, 6-year trial comparing dual-chamber pacing (DDDR) and ventricular pacing (VVIR) in sinus node dysfunction, demonstrated no difference in death or stroke and modest reductions in heart failure hospitalization (HFH) and atrial fibrillation (AF) with DDDR pacing. However, a moderate proportion of VVIR-randomized patients were temporarily or permanently crossed over to DDDR pacing. METHODS: Intent-to-treat (ITT) analyses compared treatment arms by randomized pacing mode. On-treatment analyses used time-dependent covariates to account for all crossovers. All analyses used Cox proportional hazards models and included covariates prespecified in the study design: age, gender, Charlson index, and prior stroke, heart failure, myocardial infarction, supraventricular tachyarrhythmia, and ventricular tachycardia or fibrillation. RESULTS: Of 996 VVIR-randomized patients, 375 (38%) were DDDR paced at some time, accounting for 27% of follow-up days among all VVIR-randomized patients. Of 1,014 DDDR-randomized patients, 53 (5%) were VVIR paced at some time, accounting for 1.5% of follow-up days among all DDDR-randomized patients. On-treatment analyses showed slightly lower hazard ratios favoring DDDR versus VVIR compared with ITT: death or stroke 0.88 (on-treatment) versus 0.91 (ITT); death 0.94 versus 0.95; stroke 0.74 versus 0.81; HFH 0.72 versus 0.73; and AF 0.72 versus 0.77. Interpretation of treatment effects was unchanged. CONCLUSIONS: Although treatment crossovers accounted for >25% of follow-up time in the VVIR-randomized group, this did not affect study results. End point comparisons between randomized modes are accurate reflections of DDDR versus VVIR pacing in this study population.

Aged↗
PubMed2006

Comparing classifications of death in the Mode Selection Trial: agreement and disagreement among site investigators and a clinical events committee.

Clinical events committees (CECs) are the current standard for endpoint adjudication in clinical trials. However, little data exist with which to compare CEC and site investigator determinations or to evaluate internal agreement among CEC members. Using data from the Mode Selection Trial in Sinus Node Dysfunction (MOST), we analyzed classifications of death in order to compare internal agreement among CEC physician reviewers and agreement between the CEC and site investigators. Death was classified at 2 levels: by major cause (cardiac, noncardiac, or unknown) and by minor subclassification of the major classifications. Reviewer agreement was tabulated at the major and minor levels, and standard and weighted kappa statistics were calculated. Disagreement at both levels was also determined. Individual decision-making was tabulated in terms of frequency in classifying death as unknown. All 404 deaths were classified by the CEC. Site investigators determined major classifications in 382 cases and minor classification in 379 cases. The CEC and the site investigators disagreed in classifying 41 cases (10.7%) at the major level and 117 (30.9%) at the minor level. CEC reviewers disagreed internally at the major level in 64 cases (15.8%), at the minor level in 63 cases (15.6%), and at any level in 127 cases (31.4%) (kappa = 0.60, 95% confidence interval (CI) [0.55, 0.66]; weighted kappa = 0.66, 95% CI [0.62, 0.75]). In resolving internal disagreements, the full CEC agreed with 1 of 2 CEC reviewers in 85.9% of cases. Disagreements occurred between site investigators and CEC reviewers in classifying deaths. Endpoint determination and decision-making varied among individual CEC reviewers, but second-tier reviews by the full CEC resolved all disagreements. These findings support continued use of CECs for endpoint adjudication in clinical trials.

Cause of Death↗
PubMed2006

Pacemaker implantation and quality of life in the Mode Selection Trial (MOST).

BACKGROUND: Dual-chamber pacemakers restore AV synchrony compared with ventricular pacemakers, but the effects on health-related quality of life (QOL) are uncertain. OBJECTIVES: The purpose of this study was to assess the effect of pacemaker implantation, clinical factors, and pacing mode on QOL. METHODS: The Mode Selection Trial (MOST) randomized 2,010 patients with sinus node dysfunction to rate-modulated right ventricular (VVIR) or dual-chamber (DDDR) pacing. A longitudinal analysis of serial QOL measures (Short Form-36 [SF-36], Specific Activity Scale, and time trade-off utility) was performed. In patients who crossed over from VVIR to DDDR because of severe pacemaker syndrome, the last known QOL prior to crossover was carried forward. RESULTS: Pacemaker implantation resulted in substantial improvement in almost all QOL measures. Subjects 75 years or older experienced significantly less improvement in functional status and physical component summary scores than did younger subjects. In longitudinal analyses of the effect of pacing mode on QOL, significant improvement in three SF-36 subscales was observed with DDDR pacing compared with VVIR pacing: role physical [62.8 points (95% confidence interval [CI] 60.2, 65.5) vs 56.4 (95% CI 53.7, 59.1)], role emotional [85.0 (95% CI 82.9, 87.0) vs 81.9 (95% CI 79.9, 84.0)], and vitality [51.8 (95% CI 50.3, 53.3) vs 49.3 (95% CI 47.8, 50.7)], but not in other SF-36 subscales, the Specific Activity Scale, or utilities. The gains in QOL were larger than the declines associated with 1 year of aging but smaller than those associated with heart failure. CONCLUSION: Pacemaker implantation improved health-related QOL. The mode selected was associated with much smaller, but significant, improvements in several domains, particularly role physical function.

Aged↗
PubMed2006

The association of the heart failure score with mortality and heart failure hospitalizations in elderly patients: insights from the Mode Selection Trial (MOST).

BACKGROUND: Patient and physician preferences as well as cost favor an increasingly higher threshold for hospital admission for heart failure (HF) treatment. This trend risks masking the severity and prevalence of HF as hospitalization for HF may decrease. METHODS: Heart Failure Score (HFS) has 4 ordinal subscales assessing (1) HF symptoms, physical signs of left (2) and (3) right HF, and (4) therapy changes for HF. Heart Failure Score was calculated for 1257 of 2010 (63%) patients enrolled in the MOST trial in sinus node dysfunction, who survived and had complete first-year HFS data at 4 postpacemaker implant visits (1, 3, 6, and 12 months). Heart Failure Score was summed and ranged from 0 to 14, with lower scores representing less HF. RESULTS: There were 1257 patients (median age 74 years [interquartile range 68-79], 47% were women, 61% had hypertension, 20%, diabetes mellitus, and 23%, prior myocardial infarction). The median HFS accumulated during 1 year was 4 (interquartile range 1-8). Of patients with a benign first year, those with a higher HFS were more likely to die during subsequent follow-up compared with patients with lower HFS (hazard ratio 1.07, 95% CI 1.04-1.10 for each 1-point increase, P < .001). CONCLUSIONS: Increasing HFS is associated with an increased risk of mortality in mostly elderly patients without pre-existing HF. Heart Failure Score may be a useful surrogate HF end point for clinical trials.

Aged↗
PubMed2006

Comparative lipid-lowering effects of policosanol and atorvastatin: a randomized, parallel, double-blind, placebo-controlled trial.

BACKGROUND: Policosanol, commonly derived from purified sugar cane wax, has been reported to exert lipid-lowering effects. Policosanol is available in the United States as a nutritional supplement despite no US research clinical experience. This trial was designed to rigorously establish the lipid-lowering efficacy of policosanol as monotherapy and its potential additive and possibly synergistic effects when added to statin therapy. METHODS: A randomized, parallel, double-blind, double-dummy, placebo-controlled design was used. Patients with low-density lipoprotein cholesterol (LDL-C) levels from 140 to 189 mg/dL were assigned into 1 of 4 groups to receive policosanol 20 mg, atorvastatin 10 mg, combination therapy, or placebo for 12 weeks. RESULTS: A total of 99 patients were examined. Baseline characteristics were similar among all treatment groups. Policosanol (20 mg/d for 12 weeks) did not significantly change plasma total cholesterol, LDL-C, high-density lipoprotein cholesterol, or triglyceride levels when compared with baseline values or with values of placebo-treated patients. Atorvastatin (10 mg/d for 12 weeks) reduced total cholesterol by 27% and LDL-C by 35%. Addition of policosanol to atorvastatin failed to produce any further reduction in lipid levels above that of atorvastatin alone. Policosanol was safe and did not affect liver enzyme or creatinine phosphokinase levels. CONCLUSIONS: Policosanol did not reduce LDL-C or total cholesterol levels either alone or in combination with atorvastatin. This observation supports the need for systematic evaluation of available products containing policosanol to determine their clinical lipid-lowering efficacy under rigorous experimental conditions. We propose that policosanol should be added to the list of nutritional supplements lacking scientific validity to support their use.

Adult↗
PubMed2005

Association of prolonged QRS duration with death in a clinical trial of pacemaker therapy for sinus node dysfunction.

BACKGROUND: Prolonged QRS duration (QRSd) is an important prognostic indicator for death and heart failure hospitalization in patients with systolic heart failure. The relationship of baseline QRSd to death and heart failure hospitalization in patients with sinus node dysfunction who require pacemaker therapy is unknown. METHODS AND RESULTS: Baseline QRSd from 12-lead ECGs before pacemaker implantation were analyzed in the Mode Selection Trial (MOST), a 6-year, 2010-patient randomized trial of dual-chamber versus ventricular pacing in sinus node dysfunction. Baseline QRSd was > or =120 ms in 23.4% of patients and was associated with older age, lower ejection fraction, cardiomyopathy, and prior heart failure. Adjusted Cox models demonstrated baseline QRSd > or =120 ms was a strong independent predictor of death (hazard ratio [95% CI] 1.35 [1.07, 1.70], P=0.010) but not heart failure hospitalization. The risk of death increased with increased QRSd from 60 to 120 ms (P=0.002 and hazard ratio [95% CI] 1.14 [1.05, 1.23] for 10-ms increase in this range) after adjustment for other death predictors. CONCLUSIONS: Baseline QRSd > or =120 ms was associated with increased risk of death during pacemaker therapy for sinus node dysfunction.

Aged↗
PubMed2005

Cost-effectiveness of dual-chamber pacing compared with ventricular pacing for sinus node dysfunction.

BACKGROUND: Compared with single-chamber ventricular pacing, dual-chamber pacing can reduce adverse events and, as a result, improve quality of life in patients paced for sick sinus syndrome. It is not clear, however, how these benefits compare with the increased cost of dual-chamber pacemakers. METHODS AND RESULTS: We used 4-year data from a 2010-patient, randomized trial to estimate the incremental cost-effectiveness of dual-chamber pacing compared with ventricular pacing and then projected these findings over the patients' lifetimes by using a Markov model that was calibrated to the first 5 years of in-trial data. To assess the stability of the findings, we performed 1000 bootstrap analyses and multiple sensitivity analyses. During the first 4 years of the trial, dual-chamber pacemakers increased quality-adjusted life expectancy by 0.013 year per subject at an incremental cost-effectiveness ratio of 53,000 dollars per quality-adjusted year of life gained. Over a lifetime, dual-chamber pacing was projected to increase quality-adjusted life expectancy by 0.14 year with an incremental cost-effectiveness ratio of approximately 6800 dollars per quality-adjusted year of life gained. In bootstrap analyses, dual-chamber pacing was cost-effective in 91.9% of simulations at a threshold of 50,000 dollars per quality-adjusted year of life and in 93.2% of simulations at a threshold of 100,000 dollars. Its cost-effectiveness ratio was also below this threshold in numerous sensitivity analyses that varied key estimates. CONCLUSIONS: For patients with sick sinus syndrome requiring pacing, dual-chamber pacing increases quality-adjusted life expectancy at a cost that is generally considered acceptable.

Aged↗
PubMed2005

Prognostic use of echocardiography 1 year after a myocardial infarction.

BACKGROUND: Left ventricular (LV) and right ventricular (RV) function are known predictors of morbidity and mortality after an acute myocardial infarction (MI). However, the prognostic use of a late evaluation of cardiac function after an MI remains unclear. METHODS: We analyzed echocardiograms obtained 1 year after MI in patients with LV dysfunction at baseline (ejection fraction [EF] < or = 40%) from 291 patients enrolled in the SAVE echocardiographic substudy who did not develop heart failure (HF) or a recurrent MI during this first year. Left ventricular EF and RV fractional area change were assessed. RESULTS: After a median follow-up of 22 months after the 1-year echocardiogram, a low LVEF (< 30%) at 1 year was associated with an increased risk of death and/or HF (hazards ratio [HR] 2.7, 95% CI 1.3-5.3). Presence of RV dysfunction was also associated with an increased risk of death (HR 8.9, 95% CI 3.5-22.1), development of HF (HR 7.1, 95% CI 3.4-15.0), and the composite end point of death or HF (HR 7.6, 95% CI 4.1-14.2). In multivariate analyses, both low LVEF and RV dysfunction remained independently predictive of the composite end point of death or HF. Patients with biventricular dysfunction were at the greatest risk of death and/or HF (HR 19.4, 95% CI 8.2-46.0) in follow-up. CONCLUSIONS: In a stable population of survivors of MI, impaired LV and RV function at 1 year after MI are independently and additively predictive of increased risk of HF or death.

Female↗
PubMed2005

Design and methodology of the Occluded Artery Trial (OAT).

Experimental and clinical studies have suggested that late opening of an infarct-related artery (IRA) after myocardial infarction (MI) could improve clinical outcome. However, the suggestive observational data are limited by selection biases. Indeed, most small randomized studies have not demonstrated benefit. Thus, there is no recommendation for routine late opening of the IRA in current national guidelines for management of stable post-MI patients. The OAT is designed to test the hypothesis that opening a totally occluded IRA 3 to 28 days after MI in high-risk asymptomatic patients will improve clinical outcome and be cost-effective. The primary end point is the first occurrence of recurrent MI, hospitalization/treatment of New York Heart Association class IV congestive heart failure, or death. Trial background, design, and preliminary baseline characteristics of 2027 randomized patients are presented. Eligible patients are randomly assigned in equal proportions to optimal evidence-based medical care or optimal care plus late opening of the IRA using percutaneous coronary intervention of the occluded IRA. Treatment groups will be compared using intent-to-treat analysis. The results of OAT should have broad clinical impact by defining an evidence-based approach to the asymptomatic, high-risk, post-MI patient with an occluded IRA. If the efficacy and cost-effectiveness of percutaneous coronary intervention are established, then a policy of routinely seeking and opening persistently occluded IRAs could be advocated. If not, this strategy should be avoided in this large subgroup of post-MI patients.

Adult↗
PubMed2005

Heart failure hospitalization is more common in pacemaker patients with sinus node dysfunction and a prolonged paced QRS duration.

OBJECTIVES: The purpose of this study was to determine whether a prolonged paced QRS duration increases the risk of cardiac dysfunction. BACKGROUND: Right ventricular apical pacing mimics left bundle branch block, results in a prolonged QRS duration of variable duration, and causes ventricular desynchronization. METHODS: In the Mode Selection Trial (MOST), QRS duration was measured in patients who had at least one paced ventricular complex recorded on 12-lead ECG within 3 months of enrollment (early) and after 9 months (late). Clinical endpoints including heart failure hospitalization, mortality, and atrial fibrillation were analyzed. A total of 1,026 patients were included in the analysis. Median age was 75 years (25th, 75th percentiles = 69, 80) and median ejection fraction prior to implant was 55% (45, 60). The cumulative percent ventricular pacing (DDDR and VVIR) was 81% over a median follow-up of 33 months. During period, 123 patients had heart failure hospitalization, 197 died, and 261 patients had atrial fibrillation. RESULTS: Cox proportional hazards models demonstrated that paced QRS duration was a strong predictor of heart failure hospitalization (hazard ratio 1.15; 95% confidence interval 1.07,1.23) for each 10-ms increase in paced QRS duration (P = .001). The increased risk was unaffected by adjustment for other known predictors of heart failure hospitalization in the study. Paced QRS duration was not significant for mortality (P = .41) or atrial fibrillation (P = .20) when baseline QRS duration and other predictors were included. CONCLUSIONS: Paced QRS duration is a significant, independent predictor of heart failure hospitalization in patients with sinus node dysfunction. A very long paced QRS duration is associated with increased heart failure hospitalization.

Aged↗
PubMed2005

Treatment and prevention of atrial fibrillation with non-antiarrhythmic pharmacologic therapy.

Atrial fibrillation is one of the most frequent heart rhythm disturbances found in clinical practice. Anticoagulation, rate control, cardioversion, and ablative procedures have been the mainstay of treatment. The frequent recurrence of atrial fibrillation and the side effects when antiarrhythmic drugs are used have led to dissatisfaction with available treatment of this arrhythmia. Pharmacologic therapy with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, statins, and perhaps aldosterone and calcium channel blockers may have a role in the prevention of atrial fibrillation onset and recurrence. We summarize the possible biologic mechanisms and the clinical observations supporting the use of non-antiarrhythmic medications in the prevention of atrial fibrillation.

Angiotensin Receptor Antagonists↗
PubMed2005

Echocardiographic comparison of cardiopulmonary resuscitation (CPR) using periodic acceleration (pGz) versus chest compression.

OBJECTIVE: This investigation compared the effects of conventional cardiopulmonary resuscitation (CPR) using an automated Thumper chest compression device to periodic acceleration CPR (pGz-CPR) on early post-resuscitation ventricular function assessed by echocardiography, in an adult pig model of CPR. BACKGROUND: Whole body periodic acceleration along the spinal axis (pGz) is a new method of cardiopulmonary resuscitation (CPR). Biomechanical forces and biochemical release produced by pGz impart ventilation and increase blood flow. Our laboratory has reported normal neurological and cardiovascular function 48 h after return of spontaneous circulation in animals that have undergone 22 min of pGz-CPR. METHODS: Ventricular fibrillation (VF) was induced in 16 animals (25-35 kg). After 3 min of non-interventional period, the animals were randomized to receive either pGz-CPR or Thumper-CPR for 15 min. After 18 min of VF, a single dose of vasopressin and bicarbonate were administered and defibrillation attempted. An echocardiogram was performed at baseline and serially for 6h. Ejection fraction (EF), fractional shortening (FS) and wall motion were assessed by 2D and M-mode echocardiography. RESULTS: Return of spontaneous circulation to 360 min occurred in 5/8 (62%) of the animals receiving Thumper-CPR and in 7/8 (88%) receiving pGz-CPR. FS and EF were impaired after CPR, but pGz-CPR animals had less impairment than Thumper-CPR animals. Further, wall motion score index (WMSI) was more impaired after Thumper-CPR and remained as such even 6h post-CPR. CONCLUSION: pGz holds promise as a new method for CPR with better left ventricular (LV) function post-CPR than the more traditional chest compression method.

Acceleration↗
PubMed2005

Clinical and quality of life comparison of accelerometer, piezoelectric crystal, and blended sensors in DDDR-paced patients with sinus node dysfunction in the mode selection trial (MOST).

INTRODUCTION: Permanent pacemakers are capable of increasing heart rate in response to physical activity by a variety of sensors including accelerometers, piezoelectric crystals, or blended sensors. The impact of these different physiologic sensors on cardiovascular events and quality of life is not known. METHODS: Of 2,010 patients randomized in the Mode Selection Trial, 1,245 patients were selected with the most commonly used pacemakers with these three sensors. Clinical characteristics and quality of life were compared between groups at baseline, 3 months, and then yearly. RESULTS: There were 449 patients with an accelerometer sensor device, 682 with a piezoelectric sensor, and 114 with a blended sensor. The groups were similar in terms of age (mean 74 years), gender, and cardiac risk factors but differences existed in weight, heart rate, mitral regurgitation, revascularization history, and drug therapy. The median ventricular pacing frequency was 80% (25th, 75th percentiles 42, 97). After a median follow-up of 33.1 months, the risk of death, heart failure hospitalization, atrial fibrillation, and the combined endpoint of mortality and stroke was not significantly different between the sensor types, after adjustment for baseline differences. Quality of life analyses demonstrated that patients with blended sensors had significantly worse (P < 0.01) physical function than did patients with the other two sensor systems. Moreover, patients receiving blended sensors had the poorest absolute scores, without reaching statistical significance, on 9 of 13 quality of life measures after adjusting for differences in the groups. CONCLUSION: We found no significant differences among the three most utilized sensors in clinical endpoints. Those patients who received blended sensors had worse physical function quality of life scores. However, clinical selection of the most sophisticated sensor for the most ill patients cannot be excluded as an explanation of these results.

Aged↗