A Novel Cause of Acute Coronary Syndrome Due to Dynamic Extrinsic Coronary Artery Compression by a Rib Exostosis: Multimodality Imaging Diagnosis.

We report a case of acute coronary syndrome secondary to intermittent extrinsic compression of the left anterior descending coronary artery by inward-pointing rib exostosis in an 18-year-old woman during forceful repeated expiration in labour. The diagnosis was achieved using multimodality noninvasive cardiac imaging. In particular, we demonstrated the novel role of expiratory-phase cardiac computed tomography in confirming the anatomical relationship of the bony exostosis to the left anterior descending coronary artery. The case reminds us the heart and mediastinum move dynamically, relative to the bony thorax, throughout the respiratory cycle, and that changes in cardiac physiology in pregnancy may become pathological.

Partial anomalous left pulmonary artery with associated bronchial anomalies in a patient with repaired Tetralogy of Fallot.

We present a 28 year old man with repaired Tetralogy of Fallot who underwent CT imaging prior to pulmonary valve replacement. CT demonstrated a partial anomalous LPA with associated bronchial anomalies and normal variant pulmonary venous drainage. The case demonstrates the utility of multislice CT in delineating 3-dimensional vascular and bronchial anatomy in these complex anomalies.

A randomized, controlled trial of C0- Vs C2-guided therapeutic drug monitoring of cyclosporine in stable heart transplant patients.

BACKGROUND: Cyclosporine monitoring using 2-hour post-dose samples (C2) is thought to be more efficacious than using pre-dose levels (C0) in managing immunosuppression for transplant patients. We evaluated the effect of C2 monitoring on cyclosporine dose and clinical parameters in stable heart transplant patients. METHODS: 125 stable heart transplant patients were randomized to C0 or C2 monitoring of cyclosporine levels for a period of six months. All patients had both C0 and C2 samples taken, and clinicians were blinded to one of the samples depending on randomization. The primary endpoint was the relative change in cyclosporine (Neoral) dose during the study period and secondary endpoints were change in creatine clearance, mortality, infection, and acute rejection. RESULTS: There was a significant decrease in the cyclosporine dose for the C2 group as compared with the C0 group (-11 mg/day and -26 mg/day respectively, p = 0.0025). No proven rejection episodes occurred in either group and there was no significant difference in the incidence of infection (C0 6, C2 10; p = 0.14), the change in renal function (change in creatine clearance C(0) +0.54 ml/min; C2 -0.16 ml/min; p = 0.61), the number of blood tests or dose adjustments between groups over the study period. Analysis of the blinded samples revealed that the reduction of cyclosporine dose in the C2 group could not be accounted for by reduced immunosuppression . CONCLUSION: C2 monitoring allows a significant cyclosporine dose reduction without compromising patient outcome in stable heart transplant patients. Further studies are required to ascertain whether this dose reduction can be translated into clinical benefit.

A deer (subfamily Cervinae) genetic linkage map and the evolution of ruminant genomes.

Comparative maps between ruminant species and humans are increasingly important tools for the discovery of genes underlying economically important traits. In this article we present a primary linkage map of the deer genome derived from an interspecies hybrid between red deer (Cervus elaphus) and Père David's deer (Elaphurus davidianus). The map is approximately 2500 cM long and contains >600 markers including both evolutionary conserved type I markers and highly polymorphic type II markers (microsatellites). Comparative mapping by annotation and sequence similarity (COMPASS) was demonstrated to be a useful tool for mapping bovine and ovine ESTs in deer. Using marker order as a phylogenetic character and comparative map information from human, mouse, deer, cattle, and sheep, we reconstructed the karyotype of the ancestral Pecoran mammal and identified the chromosome rearrangements that have occurred in the sheep, cattle, and deer lineages. The deer map and interspecies hybrid pedigrees described here are a valuable resource for (1) predicting the location of orthologs to human genes in ruminants, (2) mapping QTL in farmed and wild deer populations, and (3) ruminant phylogenetic studies.