Israel Medical Association Journal

Background: Surgical repair of tetralogy of Fallot may leave the patient with pulmonary regurgitation causing eventual right ventricle dilatation and dysfunction. Predicting clinical deterioration may help to determine the best timing for intervention.

Objectives: To assess whether the clinical and humoral status of patients in the second decade after repair of ToF[1] is worse than that of patients in the first decade after repair.

Methods: Twenty-one patients with repaired ToF underwent clinical assessment, electrocardiogram, echocardiogram and measurement of plasma B-type natriuretic peptide and N-terminal pro-BNP[2] as well as the 6 minute walk distance test. Patients were divided into two groups: group A – less than 10 years after repair (n=10, age < 12 years old), and group B – more than 10 years after repair (n=11, age > 12 years old). The age at repair was similar in both groups.

Results: In all but one patient the distance in the 6 min walk test was less than the minimum for age. RV[3] end-diastolic volume and the 6 min walk test correlated with age. NT-proBNP[4] levels were significantly higher in the ToF group compared to 26 healthy controls (P < 0.0001) and were inversely correlated with RV ejection fraction. Comparison of the two groups showed no difference in RV end-diastolic volume indexed for body surface area, pulmonary regurgitation severity, right or left ventricular myocardial performance index, RV ejection fraction, QRS duration, or 6 min walk indexed to minimum for age.

Conclusions: In this group of patients with similar age at operation and pulmonary regurgitation severity, most clinical, echocardiographic and humoral parameters were not worse in the second decade after repair of ToF. These data suggest that very early pulmonary valve replacement may not be of benefit.

Objectives: To evaluate the safety and efficacy of external counter-pulsation therapy in heart failure patients.

Methods: Fifteen symptomatic heart failure patients (subsequent to optimal medical and device therapy) underwent 35 hourly sessions of ECPT[1] over a 7 week period. Before and after each ECPT session we performed pro-B-type natriuretic peptide and brachial artery function studies, administered a quality of life questionnaire, and assessed exercise tolerance and functional class.

Results: Baseline left ventricular ejection fraction was 28.1 ± 5.8%. ECPT was safe and well tolerated and resulted in a reduction in pro-BNP[2] levels (from 2245 ± 2149 pcg/ml to 1558 ± 1206 pcg/ml, P = 0.022). Exercise duration (Naughton protocol) improved (from 720 ± 389 to 893 ± 436 seconds, P = 0.0001), along with functional class (2.63 ± 0.6 vs. 1.93 ± 0.7, P = 0.023) and quality of life scores (54 ± 22 vs. 67 ± 23, P = 0.001). Nitroglycerine-mediated brachial vasodilatation increased (11.5 ± 7.3% vs. 15.6 ± 5.2%, P =0.049), as did brachial flow-mediated dilation (8.35 ± 6.0% vs. 11.37 ± 4.9%, P = 0.09).

Conclusions: ECPT is safe for symptomatic heart failure patients and is associated with functional and neurohormonal improvement. Larger long-term randomized studies with a control arm are needed to confirm these initial encouraging observations.

Objectives: To test whether an early change in neurohormonal and inflammatory markers after implantation can predict the clinical response to CRT.

Methods: The study group included 32 patients with advanced symptomatic systolic heart failure and a prolonged QRS complex and who were assigned to undergo CRT. Baseline plasma levels of B-type natriuretic peptide and high sensitivity C-reactive protein were determined in the peripheral venous blood and coronary sinus. Post-implantation levels were determined 2 weeks post-procedure in the PVB[2]. Baseline levels and their change in 2 weeks were correlated with all-cause mortality and hospitalization for congestive heart failure.

Results: At baseline, coronary sinus levels of BNP[3] but not hsCRP[4] were significanly elevated compared to the PVB. Compared to baseline levels, BNP and hsCRP decreased significantly within 2 weeks after the implantation (BNP mean difference 229.1 ± 102.5 pg/ml, 95% confidence interval 24.2–434, P < 0.0001; hsCRP mean difference 5.2 ± 2.4 mg/dl, 95% CI[5] 0.3–10.1, P = 0.001). During a mean follow-up of 17.7 ± 8.2 months 6 patients died (18.7%) and 12 (37.5%) were hospitalized due to exacerbation of CHF[6]. Baseline New York Heart Association and CS[7] BNP levels predicted CHF-related hospitalizations. HsCRP levels or their change over 2 weeks did not predict all-cause mortality or hospitalizations.

Conclusions: BNP levels in the CS and peripheral venous blood during biventricular implantation and 2 weeks afterwards predict cilinical response and may guide patient management.

Intestinal adaptation is the term applied to progressive recovery from intestinal failure following a loss of intestinal length. The regulation of intestinal adaptation is maintained through a complex interaction of many different factors. These include nutrients and other luminal constituents, hormones, and peptide growth factors. The current paper discusses the role of peptide growth factors in intestinal adaptation following massive small bowel resection. This review focuses on the mechanisms of action of peptide growth factors in intestinal cell proliferation, and summarizes the effects of these factors on intestinal regrowth in an animal model of short bowel syndrome.

Background: Superantigens produced by Staphylococcus aureus and Streptococcus pyogenes are among the most lethal of toxins. Toxins in this family trigger an excessive cellular immune response leading to toxic shock.

Objectives: To design an antagonist that is effective in vivo against a broad spectrum of superantigen toxins.

Methods: Short peptide antagonists were selected for their ability to inhibit superantigen-induced expression of human genes for cytokines that mediate shock. The ability of these peptides to protect mice against lethal toxin challenge was examined.

Results: Antagonist peptide protected mice against lethal challenge with staphylococcal enterotoxin B and toxic shock syndrome toxin-1, superantigens that share only 6% overall amino acid homology. Moreover, it rescued mice undergoing toxic shock. Antagonist peptides show homology to a β-strand/hinge/a-helix domain that is structurally conserved among superantigens, yet remote from known binding sites for the major histocompatibility class II molecule and T cell receptor that function in toxic T cell hyperactivation.

Conclusions: The lethal effect of superantigens can be blocked with a peptide antagonist that inhibits their action at the top of the toxicity cascade, before activation of T cells occurs. Superantigenic toxin antagonists may serve not only as countermeasures to biologic warfare but may be useful in the treatment of staphylococcal and streptococcal toxic shock, as well as in some cases of septic shock.