Rehabilitation of the coronary artery disease patient: capturing patients

Poor use of cardiac rehabilitation among older adults: a self-regulatory model for tailored interventions

BACKGROUND

A greater number of older adults now live with coronary heart disease (CHD). This poses a significant public health problem, because older adults are at high risk for CHD-related mortality and morbidity. Overwhelming data support the benefits of cardiac rehabilitation for secondary prevention, yet only a small portion of eligible older adults receive it.

METHODS AND RESULTS

Whereas many studies examined factors that affect the use of cardiac rehabilitation among older adults, few interventions aimed to improve their cardiac rehabilitation participation rates. A substantial body of evidence indicates that an individual's illness perceptions play a pivotal role in health behavior, and may be a promising target for intervention. Drawing from the theoretic and empiric findings of others, a self-regulatory model is proposed that explicates how CHD perceptions of older adults may influence participation in cardiac rehabilitation.

CONCLUSION

The model may provide a useful guide for the development of effective interventions tailored to older adults.

Recombinant nematode anticoagulant protein c2, an inhibitor of tissue factor/factor VIIa, attenuates coagulation and the interleukin-10 response in human endotoxemia

The tissue factor-factor (F)VIIa complex (TF/FVIIa) is responsible for the initiation of blood coagulation under both physiological and pathological conditions. Recombinant nematode anticoagulant protein c2 (rNAPc2) is a potent inhibitor of TF/FVIIa, mechanistically distinct from tissue factor pathway inhibitor. The first aim of this study was to elucidate the pharmacokinetics and pharmacodynamics of a single intravenous (i.v.) dose of rNAPc2. The second aim was to study its effect on endotoxin-induced coagulation and inflammation. Initially, rNAPc2 was administered to healthy volunteers in three different doses. There were no safety concerns and the pharmacokinetics were consistent with previous studies, in which rNAPc2 was administered subcutaneously. rNAPc2 elicited a dose-dependent reduction of the endogenous thrombin potential and a selective prolongation of prothrombin time. Subsequently, the effect on endotoxin-induced coagulation and inflammation was studied. The administration of rNAPc2 completely blocked the endotoxin-induced thrombin generation, as measured by plasma prothrombin fragment F1+2. The endotoxin-induced effect on fibrinolytic parameters such as plasmin-antiplasmin complexes and plasminogen activator inhibitor type 1 was not affected by rNAPc2. The administration of rNAPc2 attenuated the endotoxin-induced rise in interleukin (IL)-10, without affecting the rise in other cytokines. In conclusion, rNAPc2 is a potent inhibitor of TF/FVIIa, which was well tolerated and could safely be used intravenously in this Phase I study in healthy male volunteers. A single i.v. dose rNAPc2 completely blocked endotoxin-induced thrombin generation without affecting the fibrinolytic response. In addition, rNAPc2 attenuated the endotoxin-induced rise in IL-10, without affecting the rises in other cytokines.

Attendance and Graduation Patterns in a Group-model Health Maintenance Organization Alternative Cardiac Rehabilitation Program

PURPOSE

Poor rates of participation in cardiac rehabilitation programs are well documented, especially among women and older patients. The Colorado Kaiser Permanente Cardiac Rehabilitation (KPCR) program is a home-based, case-managed, goal-oriented program with an active recruitment process and unlimited program length. This study evaluated the participation rates for the program and the predictors of attendance and graduation.

METHODS

Patients hospitalized with acute myocardial infarction, coronary artery bypass graft, and percutaneous coronary intervention from June 1999 to May 2000 (n = 1030) were identified from the administrative database, and the proportion captured by the KPCR staff was determined. Subsequent attendance and graduation patterns were evaluated.

RESULTS

Nearly 94% of patients with one of the three aforementioned conditions were identified by the rehabilitation staff, and 41% of all patients attended the KPCR program. More than 75% of the patients who participated went on to graduate from the program. Gender comparisons showed no difference in participation between men (66.8%) and women (59.7%) (P =.07). Participation rates were inversely associated with age, yet age was not associated with graduation from the program. Surgical interventions and two or more events experienced within the first 4 weeks of the index event were the strongest predictors of attendance and graduation from the KPCR program.

CONCLUSIONS

Innovative approaches for the capture and retention of patients in cardiac rehabilitation programs are urgently needed. The alternative program evaluated in this study showed little difference in participation between men and women, yet participation among older patients remained poor. Overall, patients who underwent surgical interventions or multiple events were more likely to attend and graduate from the program.

Ability of recombinant factor VIIa to generate thrombin during inhibition of tissue factor in human subjects

BACKGROUND

In view of the central role of the tissue factor-factor VIIa pathway in the initiation of blood coagulation, novel therapeutic strategies aimed at inhibiting this catalytic complex are currently being evaluated. A limitation of this new class of anticoagulants may be the lack of an appropriate strategy to reverse the effect if a bleeding event occurs. The aim of this study was to investigate the in vivo potential of recombinant factor VIIa (rVIIa) to induce thrombin generation in healthy subjects pretreated with recombinant nematode anticoagulant protein c2, a specific inhibitor of the tissue factor-factor VIIa complex, in a double-blind randomized crossover study.

METHODS AND RESULTS

Administration of nematode anticoagulant protein c2 (3.5 microgram/kg) caused a prolongation of the prothrombin time from 13.7+/-0.6 to 16.9+/-1.2 seconds. The subsequent injection of rVIIa (90 microgram/kg) resulted in an immediate and complete correction of the prothrombin time and a marked generation of thrombin, reflected by increased levels of prothrombin activation fragment F1+2 and thrombin-antithrombin complexes from 0.75+/-0.64 to 3.29+/-6.3 nmol/L and from 2.4+/-0.6 to 10.7+/-3.9 microgram/mL, respectively. Factor X and IX activation peptides showed a 3.5-fold and a 3.8-fold increase, respectively, after the administration of rVIIa in the presence of nematode anticoagulant protein c2.

CONCLUSIONS

During treatment with an inhibitor of the tissue factor-factor VIIa complex, the infusion of rVIIa resulted in thrombin generation. Our results indicate that rVIIa may be a good candidate as an antidote for inhibitors of tissue factor.