Single lead ST-segment recovery: a simple, reliable measure of successful fibrinolysis after acute myocardial infarction

Background

Successful reperfusion after acute ST-elevation myocardial infarction improves prognosis. Among the different electrocardiographic markers of reperfusion, sum ST resolution is considered the hallmark of reperfusion, but is cumbersome to use.

Methods

To assess the usefulness of a single lead ST resolution at 90 minutes after fibrinolysis compared with the sum ST resolution in predicting Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow, we used prospectively collected data from the Limitation of Myocardial Injury Following Thrombolysis in Acute Myocardial Infarction (LIMIT-AMI) study. All patients had electrocardiograms recorded at presentation and 90 minutes and a coronary angiogram 90 minutes after fibrinolysis.

Results

Infarction artery patency was assessed in 238 patients with 4 different ST resolution criteria: single lead ST resolution ≥50% and ≥70% and sum ST resolution ≥50% and ≥70%. The most sensitive criteria for TIMI grade 3 flow was single lead ST resolution ≥50% (sensitivity rate, 70%; specificity rate, 54%), whereas sum ST resolution ≥70% was most the specific criteria (sensitivity rate, 45%; specificity rate, 79%). The proportion of patients with TIMI grade 3 flow was similar in all 4 ST resolution groups (P = .84). Pre-discharge infarction size and ejection fraction were also similar. No single lead or sum lead measure of ST resolution was significantly associated with an increased risk of death, heart failure, or reinfarction.

Conclusion

We propose that single lead ST-resolution ≥50% as an optimal electrocardiographic indicator for successful reperfusion 90 minutes after fibrinolysis. This simple electrocardiographic measure should be combined with bedside clinical and hemodynamic assessment to optimize decision making after fibrinolysis.     

Pre-B acute lymphoblastic leukemia cells may induce T-cell anergy to alloantigen

Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance.     

Nerve conduction studies in leprosy.

Motor and sensory nerve conduction studies have been performed on the peripheral nerves in the upper and lower limbs of 30 control subjects, and 36 subjects with leprosy from the Aboriginal population of the Northern Territory of Australia. Impairment of conduction was demonstrated in the vast majority of clinically abnormal nerves, and a large proportion of nerves which appeared clinically to be uninvolved. In a third group of subjects, abnormal conduction was demonstrated in a significant number of nerves which were considered to be clinically enlarged but in whom the diagnosis was initially in doubt. The majority of these patients were subsequently proven to have leprosy. It is concluded that nerve conduction studies are of considerable value in the diagnosis and management of leprosy.     

Discrete Choice Experiment to Estimate Breast Cancer Patients’ Preferences and Willingness to Pay for Prophylactic Granulocyte Colony-Stimulating Factors

ObjectivesRising out-of-pocket costs for cancer patients have increased shared decision making. Clinical guidelines recommend prophylactic granulocyte colony-stimulating factor (G-CSF) for patients receiving chemotherapy with a 20% or greater risk of febrile neutropenia. A discrete choice experiment was conducted to explore breast cancer patients’ preferences and willingness to pay (WTP) for prophylactic G-CSF to decrease the risk of chemotherapy-induced febrile neutropenia.MethodsAn online discrete choice experiment questionnaire survey of a national US convenience sample of self-reported breast cancer patients with prior chemotherapy treatment was conducted. Sixteen paired G-CSF treatment scenarios, each with four attributes (risk of disruption to chemotherapy schedule due to low white blood cell counts, risk of developing an infection requiring hospitalization, frequency of administration, and total out-of-pocket cost) were presented with a follow-up “no treatment” option. Participant preferences and WTP out of pocket were estimated by logistic regression.ResultsParticipants (n = 296) preferred G-CSF regimens with lower out-of-pocket costs, lower risk of chemotherapy disruption, lower risk of infection, and greater convenience (one G-CSF injection per chemotherapy cycle). Participants’ WTP was $1076 out of pocket per cycle to reduce the risk (high to low) of disrupting their chemotherapy schedule, $884 per cycle to reduce the risk (24% [high] to 7% [low]) of infection, and $851 per cycle to decrease the number of G-CSF injections (11 to 1) per cycle.ConclusionsParticipants highly valued specific features of prophylactic G-CSF treatment including maintaining their chemotherapy schedule, lowering their risk of infection, and reducing the number of injections. Physicians should consider patient preferences to inform the best treatment choices for individual patients.