CT19PTRICUSPID VALVE REPAIR IN ‘TORRENTIAL TRICUSPID REGURGITATION’ FOLLOWING PERMANENT PACEMAKER LEAD EXTRACTION – A CASE REPORT

Introduction Traumatic tricuspid regurgitation secondary to blunt chest trauma has been reported in literature. We report our experience with a case of ‘Torrential Tricuspid Regurgitation’ following permanent pacemaker lead extraction which was successfully treated with tricuspid valve repair and annuloplasty. Report A 67 year old woman was treated for Sick sinus syndrome with permanent pacemaker implant. She had three generator changes for end of life and repositioning.Erosion of generator, led cardiologist to plan lead and generator extraction with the surgical backup. During lead extraction a small piece of papillary muscle was avulsed. The patient remained hemodynamically stable in the theatre. However in ward she developed right sided cardiac failure not responding to conservative therapy. A transthoracic echo (TTE) revealed torrential tricuspid regurgitation with a freely mobile posterior leaflet with attached chordae and avulsed papillary muscle.During surgery the tricuspid valve was successfully repaired and transesophageal (TOE) images showed trivial to mild tricuspid regurgitation at the end of repair procedure. Additional procedure also included ligation of both atrial appendages and implantation of epicardial leads and pacemaker. Patient made good recovery from operation. Conclusion To the best of our knowledge this is first report of repair of tricuspid valve in ‘Torrential Tricuspid Regurgitation’ following pacemaker lead extraction. We share our experience with tricuspid valve repair technique and annuloplasty.     

Emergence and scattering of multiple neurofibromatosis (NF1)-related sequences during hominoid evolution suggest a process of pericentromeric interchromosomal transposition

Type 1 neurofibromatosis (NF1) gene encodes for a member of the GTPase activating protein family and is considered to be a tumor suppressor gene. Its very high rate of de novo mutation in humans led us to study a specific feature of this gene: the presence of numerous NF1-related sequences. According to our results, the human genome contains at least 11 NF1-related sequences, nine of which are scattered near centromeric sequences of seven different chromosomes. These NF1-related sequences, whose extent is quite varied according to loci, are unprocessed copies of the NF1 gene, and bear numerous mutations. A phylogenetic analysis of the six largest sequences indicates that they are all derived from a common ancestor, which would have appeared 22-33 million years ago, and was subsequently duplicated several times during hominoid evolution. The most recent duplication and interchromosomal transposition occurred in the last million years suggesting that the process could still be ongoing. Intriguing similarities between the evolution of alpha- satellite DNA and NF1-related sequences suggest the involvement of a common genetic mechanism for the generation and pericentric spreading of these NF1 partial copies.      

Mass media campaign--A Su Salud

A mass media health promotion program directed toward reducing future cancer trends among Mexican Americans, the largest subgroup of Hispanics in the United States, by decreasing smoking and encouraging smoking prevention and other health practices is described. Included is an outline of the program design and its significant features and a discussion of social modeling, the theoretical approach which provides a framework for the program. The development of the program, including the role focus groups played in the identification of areas to be targeted by the program, and the production and implementation of the mass media campaign based upon the targeted program areas are also discussed.     

X-linked hypophosphatemia: Normal renal function despite medullary nephrocalcinosis 25 years after transient vitamin D2-induced renal azotemia

Nephrocalcinosis (NC) detected by ultrasound is a recognized abnormality for some patients with X-linked hypophosphatemia (XLH) who received vitamin D₂ and inorganic phosphate therapy, but is commonly observed in XLH patients treated with 1,25-dihydroxyvitamin D₃ and inorganic phosphate supplementation. Nevertheless, long-term follow-up of kidney function in XLH patients with NC detected ultrasonographically has not been reported. We investigated two women with XLH, ages 31 (patient 1) and 39 (patient 2) years, each of whom had suffered at least one documented episode of vitamin D₂-induced hypercalcemia and renal azotemia during childhood. Patient 2 had also been treated with inorganic phosphate. No medications for XLH had been taken during adulthood. Renal ultrasonography at our institution demonstrated marked bilateral medullary NC in both women. No other explanation was found for their NC that apparently occurred several decades earlier from medical therapy for XLH. Detailed studies (including creatinine clearance, β₂-microglobulin excretion, and fasting urinary osmolality and acidification) revealed no impairment of kidney function in either patient. Our findings indicate that subradiographic medullary NC acquired during medical therapy for XLH may persist for decades, but with no adverse renal sequelae. Definitive (long-term) assessment of kidney function in the XLH population with NC, however, will be necessary to fully understand the risk of current medical treatment for this most common heritable form of rickets.     

Talo-patello-scaphoid osteolysis,synovitis, and short fourth metacarpals in sisters: a new syndrome?

Osteolysis syndromes are characterized by resorption of affected bones with associated swelling and pain. Various forms of multicentric osteolysis syndromes including autosomal dominant and recessive carpal-tarsal osteolysis, Torg, Fran?ois, Whyte-Hemingway, Hajdu-Cheney, Winchester, and other forms have been described. Most present in pre-school years with extensive involvement and destruction of multiple bones. We present a sister-pair, both of whom presented in early teenage, i.e., 13 and 15.5 years, respectively, with bilateral ankle, knee, and later, wrist pain. Radiological examination revealed bilateral osteolysis of tali, scaphoids, and patellae, and short fourth metacarpals in both sisters. Further investigation revealed absence of renal involvement, a normal excretion of amino acids, mucopolysaccharides and oligosaccharides, and presence of chronic synovitis in both sisters. Both parents and a younger brother were without radiographic or clinical evidence of the disease and there was no history of consanguinity. Thus, our sister-pair presented with the same carpal and tarsal bone involvement at a much later age, with evidence of chronic synovitis, along with short fourth metacarpals (brachydactyly type E changes) and without renal disease, suggesting a new syndrome with probable autosomal recessive inheritance.     

Skeletal changes in epidermal nevus syndrome: does focal bone disease harbor clues concerning pathogenesis?

Epidermal nevus syndrome (ENS) is a rare, sporadic, congenital disorder of unknown etiology featuring a complex and highly variable phenotype that can include focal or generalized skeletal disease. We describe a young man with ENS manifesting right-sided linear skin lesions, generalized weakness, diffuse osteopenia associated with hypophosphatemic rickets, and distinctive focal bone lesions ipsilateral to the skin findings. Review of the literature concerning ENS-associated skeletal disease suggested such focal bone defects are fibrous dysplasia, but our patient did not have the typical radiographic or histopathologic findings of fibrous dysplasia. Nevertheless, his circulating fibroblast growth factor 23 (FGF-23) level was elevated, likely functioning as a "phosphatonin," yet no activating mutations in GNAS previously reported in fibrous dysplasia or McCune-Albright syndrome were detected in his leukocytes or affected skin. We postulate that the focal skeletal disease, although different than fibrous dysplasia, may be a source of FGF-23 in ENS.     

Homozygosity mapping of achromatopsia to chromosome 2 using DNA pooling

Achromatopsia is an autosomal recessive disease of the retina, characterized clinically by an inability to distinguish colors, impaired visual acuity, nystagmus and photophobia. A genome-wide search for linkage was performed using an inbred Jewish kindred from Iran. To facilitate the genome-wide search, we utilized a DNA pooling strategy which takes advantage of the likelihood that the disease in this inbred kindred is inherited by all affected individuals from a common founder. Equal molar amounts of DNA from all affected individuals were pooled and used as the PCR template for short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected members of the kindred was used as a control. A reduction in the number of alleles in the affected versus control pool was observed at several loci. Upon genotyping of individual family members, significant linkage was established between the disease phenotype and markers localized on chromosome 2. The highest LOD score observed was 5.4 (theta = 0). When four additional small unrelated families were genotyped, the combined peak LOD score was 8.2. Analysis of recombinant chromosomes revealed that the disease gene lies within a 30 cM interval which spans the centromere. Additional fine-mapping studies identified a region of homozygosity in all affected individuals, narrowing the region to 14 cM. A candidate gene for achromatopsia was excluded from this disease interval by radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an essential first step in the identification of the disease-causing gene.      

The management of hypertension in Canada: a review of current guidelines, their shortcomings and implications for the future

CLINICIANS ARE EXPOSED to numerous hypertension guidelines. However, their enthusiasm for these guidelines, and the impact of the guidelines, appears modest at best. Barriers to the successful implementation of a guideline can be identified at the level of the clinician, the patient or the practice setting; however, the shortcomings of the guidelines themselves have received little attention. In this paper, we review the hypertension guidelines that are most commonly encountered by Canadian clinicians: the “1999 Canadian Recommendations for the Management of Hypertension,” “The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure” in the United States and the “1999 World Health Organization–International Society of Hypertension Guidelines for the Management of Hypertension.” The key points of these guidelines are compared and the shortcomings that may impede their ability to influence practice are discussed. The main implications for future guideline developers are outlined.