Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A review of the electrocardiograms (ECG) of 108 patients with sickle cell anemia found only 3 with patterns consistent with myocardial infarction. Two of the 3 patients with ECG infarct patterns had postmortem examination confirmation of the infarction. These two patients had no significant coronary atherosclerosis nor did the other six autopsied patients in the present series. Literature reports of postmortem examinations on patients with sickle cell anemia confirm the scarcity of coronary atherosclerosis and myocardial infarction in these patients. Forty of the 108 ECGs showed signs of left ventricular hypertrophy and 20 others had nondiagnostic ST and T wave abnormalities. Nine showed first degree AV block and four right bundle branch block.
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PMID:Myocardial infarction in sickle cell anemia. 623 6

The Brugada syndrome was first described in 1992. Palpitations and/or syncope are usually experienced during rest and increased vagal activity. [table: see text] However, in 15% of patients with Brugada syndrome, symptoms occur during physical activity. The syndrome is further characterized by a pattern of RBBB and ST-segment elevation in V1 to V2/V3 (see Table). One major and one minor criterion from the Table can serve to establish a diagnosis of Brugada syndrome. The patient presented in this report described symptoms only during physical activity. EPS confirmed the diagnosis of the Brugada syndrome, and an ICD was implanted. The clinical importance of the Brugada syndrome is that it calls attention to patients at risk for SCD. The syndrome is genetically determined and caused by mutations in the cardiac ion channels. Signal averaging that reveals late potentials can help identify persons who may be at high risk for SCD and who would thus be candidates for EPS, which can identify those at risk of SCD. The ICD is the only therapy known to help prevent SCD in patients with Brugada syndrome.
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PMID:Brugada. 1154 70

The Brugada disease, the last clinico-cardiologic entity described in the 20th century, initially called right bundle branch block syndrome with ST segment elevation from V1 to V2 or V3 and sudden cardiac death, is genetically determined in a dominant autosomal mode, and it affects the alpha subunit of the Na+ channel by alteration of chromosome 3 and mutation in the SCN5A gene. In clinical diagnosis the mentioned electrocardiographic pattern in a patient without structural heart disease and positivity in pharmacological tests are considered major criteria. As minor criteria, the following are considered: positive family history, presence of syncope with unknown origin, documented episode of VT/VF, inducibility in electrophysiologic study and positivity of genetic study. The long-standing technology of ECG, with more than a century of existence, remains as the supplementary method with highest value in diagnosis, and currently new electrocardiographic criteria are suggested, which indicate high risk of VF. Natural history indicates a somber diagnosis in symptomatic patients with a high index of arrhythmic SCD secondary to very fast polymorphic ventricular tachycardia bursts, which degenerate into VF. Asymptomatic individuals with only a Brugada-type electrocardiographic pattern have a low risk. The prognosis seems to depend more on clinical facts, since a positive electrophysiologic study has an accuracy of just around 50%. We propose that this entity should be promoted to the category of disease, since it has a characteristic set of signs and symptoms, and an identified genetic defect.
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PMID:Brugada disease: chronology of discovery and paternity. Preliminary observations and historical aspects. 1694 25

Randomized trials and observational data have consistently demonstrated the benefit of ICDs for primary prevention of SCD in patients with HF and LVSD or secondary prevention in patients with a history of prior ventricular arrhythmias or aborted SCD, most of whom have HF. Secondary and post hoc analyses of trial data, as well as observational data, generally suggest that ICD therapy is effective in most selected subpopulations, such as the elderly and patients with NYHA class IV HF symptoms, but some studies suggest that ICDs may not be as effective in women and those with severe comorbidities, such as ESRD. Although there is limited evidence for an incremental benefit achieved with dual-chamber compared with single-chamber ICDs, the former devices are placed almost twice as frequently in the United States. Finally, observational data have recently shown that ICD procedural outcomes are improved when the device is placed by an electrophysiologist and at a high-volume hospital. More recently, clinical trials have demonstrated that cardiac resynchronization therapy improves quality of life and lowers rates of HF hospitalization in patients with symptomatic HF, LVSD, and a prolonged QRS complex already receiving optimal medical management; recent trial results have also suggested a mortality benefit with CRT in this population. In addition, recent trial data suggest that CRT reduces nonfatal events among mildly symptomatic patients (NYHA class I-II); however, the cost-effectiveness of CRT in this population remains unclear. As with ICDs, secondary and post hoc analyses of trial data as well as observational data suggest that CRT remains effective in most selected subpopulations, including stable NYHA class IV patients, the very elderly, and women. Recent observational work has suggested that CRT may not benefit patients with an RBBB QRS morphology to the same extent as those with an LBBB pattern, although because more conclusive studies are currently lacking, the guidelines do not tailor the recommendations based on QRS morphology. In summary, ICDs, CRT-P, and CRT-D represent important and effective treatment modalities for select patients with HF. Additional investigation is required to better determine which patient populations most benefit from these cardiac devices and which device, implanting physician, and hospital characteristics optimize outcomes with these cardiac devices.
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PMID:Effectiveness of implantable cardioverter defibrillators and cardiac resynchronization therapy in heart failure. 2316 18

Brugada syndrome (BrS) is an inherited cardiac arrhythmic disorder, characterized by ST-segment elevation in right precordial leads V1-V2>2 mm, pseudo right bundle branch block (RBBB), T-wave inversion and an increased risk of cardiac sudden death (SCD) due to molymorphic VT. It is estimated to be responsible for 12% of SCD cases and about 20% of deaths in patients with structurally normal hearts in autopsy. Mutations in the SCN5A gene account 15-30% of all cases. Clinical, instrumental and genetic analyses were performed for 25 Russian probands with BrS (19 males and 6 female). Phenotype-genotype correlation was studied in SCN5A-positive and SCN5A-negative patients. Rare genetic variants in SCN5A gene were found in 7 of 21 Russian probands (28%). Two variants affect protein splicing (c.IVS16DS-5A>G and c.IVS24AS+1G>A), three missense mutations (p,Y87C, p.R893H and p.S1787N), one in-frame deletion p.del848l, and one non-sense-mutation p.E553X. All mutations were unique for each family. There were no clinical or instrumental parameters were found to be effective in prediction of SCN5A mutations. The protocols of genetic counceling for SCN5A-positive and SCN5A-negative families were established.
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PMID:[Clinic and genetic polymorphism of Brugada syndrome in Russian patients, caused by mutation in SCN5A gene]. 2350 84