Colonic venous malformation and portal hypertension: association,management, and review of the literature

We present a case of an adolescent with lower gastrointestinal bleeding caused by a colorectal venous malformation (VM) with concomitant portal hypertension. After an episode of massive gastrointestinal bleeding, we performed an extended right hemicolectomy and resection of the VM and selective portosystemic shunt. Here, we present the case and review the literature regarding portal hypertension and gastrointestinal vascular malformations. Additionally, we discuss the physiologic and hemodynamic effects of gastrointestinal vascular malformations on the portal system.     

Extracorporeal membrane oxygenation support of a severe metabolic crisis in a child with methylmalonic acidemia

A 9-year-old female, with mut phenotype of methylmalonic acidemia who developed severe vasoplegic shock during a metabolic crisis, was successfully supported with venoarterial extracorporeal membrane oxygenation.     

Newly detected atrial fibrillation following dual chamber pacemaker implantation

Introduction: Pacemaker (PPM)-detected atrial high-rate episodes (AHREs) of even 5-minute duration may identify patients at increased risk for stroke and death. In this study, we sought to determine the incidence of newly detected atrial fibrillation (AF defined as an AHRE ≥5 minutes) in patients following dual-chamber PPM implantation and to define the clinical predictors of developing AF.
Methods and Results: We evaluated 262 patients (142 male; age 74 ± 12 years) without documented AF who underwent PPM implantation for sinus node dysfunction (n = 122) or atrioventricular block (n = 140). Information regarding patient demographics, cardiovascular diseases, and medication history was obtained. The cumulative percentages of ventricular pacing as well as the frequency, duration, and time to first episode of an AHRE were also determined. During follow-up of 596 ± 344 days, an AHRE ≥5 minutes was detected in 77 (29%) patients. Of these, 47 (61%) patients had an AHRE ≥1 hour, 22 (29%) patients had an AHRE ≥1 day, and 12 (16%) patients had an AHRE ≥1 week. An AHRE ≥5 minutes was seen in 24% and 34% of patients at 1 year and 2 years, respectively. Among patients with sinus node dysfunction, ≥50% cumulative ventricular pacing was the only significant predictor of an AHRE ≥5 minutes (HR 2.2; CI 1.0–4.7; P = 0.04).
Conclusions: Within 1 year of PPM implantation, AF is detected in 24% of patients without history of AF. In patients with sinus node dysfunction, ≥50% cumulative right ventricular pacing is associated with a 2-fold increase in risk of developing AF.     

Right and left ventricular outflow tract tachycardias: evidence for a common electrophysiologic mechanism

Introduction: "Idiopathic" ventricular arrhythmias most often arise from the right ventricular outflow tract (RVOT), although arrhythmias from the left ventricular outflow tract (LVOT) are also observed. While previous work has elucidated the mechanism and electropharmacologic profile of RVOT arrhythmias, it is unclear whether those from the LVOT share these properties. The purpose of this study was to characterize the electropharmacologic properties of RVOT and LVOT arrhythmias.
Methods and Results: One hundred twenty-two consecutive patients  (61 male; 50.9 ± 15.2 years)  with outflow tract arrhythmias comprise this series, 100 (82%) with an RVOT origin, and 22 (18%) with an LVOT origin. The index arrhythmia was similar: sustained ventricular tachycardia (VT)  (RVOT = 28%, LVOT = 36%)  , nonsustained VT  (RVOT=40%, LVOT=23%)  , and premature ventricular complexes  (RVOT = 32%, LVOT = 41%) (P = 0.32)  . Cardiac magnetic resonance imaging and microvolt T-wave alternans results (normal/indeterminate) were also comparable. In addition, 41% with RVOT foci and 50% with LVOT foci were inducible for sustained VT (P = 0.48), and induction of VT was catecholamine dependent in a majority of patients in both groups (66% and 73%; RVOT and LVOT, respectively; P = 1.0). VT was sensitive to adenosine (88% and 78% in the RVOT and LVOT groups, respectively, P = 0.59) as well as blockade of the slow-inward calcium current (RVOT=70%, LVOT=80%; P = 1.00) in both groups.
Conclusions: Electrophysiologic and pharmacologic properties, including sensitivity to adenosine, are similar for RVOT and LVOT arrhythmias. Despite disparate sites of origin, these data suggest a common arrhythmogenic mechanism, consistent with cyclic AMP-mediated triggered activity. Based on these similarities, these arrhythmias should be considered as a single entity, and classified together as "outflow tract arrhythmias."     

HHV‐8‐related visceral Kaposi’s sarcoma following allogeneic HSCT: Report of a pediatric case and literature review

Sala I, Faraci M, Magnano GM, Sementa A, di Marco E, Garaventa A, Micalizzi C, Lanino E, Morreale G, Moroni C, Castagnola E. HHV‐8‐related visceral Kaposi’s sarcoma following allogeneic HSCT: Report of a pediatric case and literature review.
Pediatr Transplantation 2011: 15:E8–E11. © 2010 John Wiley & Sons A/S. Abstract: An HHV‐8‐related visceral KS was diagnosed in a 10‐yr‐old boy after partially matched allogeneic HSCT. This complication occurred 463 days after HSCT and involved tonsils, lymph nodes, hard palate, lung, skin, and paranasal sinuses. Treatment with pegylated liposomal doxorubicin induced long‐term remission (33 months) of this disease. HHV‐8 infection is quite frequent after HSCT, but KS, and especially its visceral form, is a very rare complication, and its association with HHV‐8 has been documented even less frequently. However, our observation suggests that HHV‐8‐related KS should be taken into consideration in the differential diagnosis of late post‐HSCT complications.