Combination of tocainide and quinidine for better tolerance and additive effects in patients with coronary artery disease

The efficacy and tolerance of tocainide used alone and in combination with quinidine were studied in 20 patients with coronary artery disease and frequent (≥30/h) ventricular premature complexes. Holter electrocardiographic monitoring was performed at baseline and during therapy with tocainide alone, quinidine alone and a combination of tocainide and quinidine. During single drug therapy, the dose of tocainide was 1,680 ± 437 mg/day and that of quinidine was 1,340 ± 235 mg/day. During combination therapy, with smaller doses of tocainide (1,350 ± 394 mg/day) and quinidine (1,060 ± 268 mg/day) in many patients, no patient had side effects. At baseline before therapy, the mean ventricular premature complexes/h were 629 ± 567, couplets/h were 23.9 ± 29.7 and nonsustained ventricular tachycardias/ 24 h were 60.5 ± 152.2. Compared with baseline values (100%), the frequency of ventricular premature complexes was reduced to 33 ± 44% with quinidine, 39 ± 30% with tocainide and 10 ± 16% with combination therapy (p < 0.01 for combination versus quinidine or tocainide alone; p = NS for quinidine versus tocainide). Individually, an effective regimen (>83% reduction of ventricular premature complexes and abolition of non-sustained ventricular tachycardia) was found in 3 (15%) of 20 patients receiving tocainide alone, in 6 (30%) receiving quinidine alone and in 16 (80%) receiving combination therapy (p < 0.01 for tocainide versus combination, quinidine versus combination; p = NS for tocainide versus quinidine).Thus, the antiarrhythmic effects of quinidine and tocainide are additive. A combination of quinidine and tocainide in smaller and well tolerated doses may avoid dose-related side effects and is more effective than either drug used alone at higher doses. Therefore, when quinidine or tocainide is ineffective because dose-related side effects limit the maximal tolerated dose, combination therapy in smaller and tolerable doses may avoid side effects and may be more effective than either drug alone at the maximal tolerated dose

Arrhythmogenic right ventricular cardiomyopathy associated with severe left ventricular involvement in a cat.

An 8-year-old, 4 kg, intact female, domestic shorthaired cat was referred for tachypnea and pleural effusion. A 24-h Holter recording showed numerous polymorphic ventricular premature complexes with left and right bundle branch block morphology. Echocardiographic examination revealed right atrial and ventricular dilation. The right ventricular free wall was thin and aneurysmal. The cat died 10 days after initiation of antiarrhythmic therapy. Gross and histopathological findings were consistent with arrhythmogenic right ventricular cardiomyopathy (ARVC) associated with severe left ventricular involvement

Utility of ambulatory electrocardiographic monitoring for predicting recurrence of sustained ventricular tachyarrhythmias in patients receiving amiodarone

The prognostic implications of changes in ventricular ectopic activity on serial 24 hour ambulatory electrocardiographic (Holter) recordings were prospectively evaluated in 107 patients with a history of sustained ventricular tachyarrhythmias treated with amiodarone for at least 30 days. Twenty-seven patients (25%) had insufficient ventricular ectopic activity < 10 ventricular premature complexes/h and no repetitive forms) on baseline Holter recordings for serial statistical analysis. In 53 (66%) of the remaining 80 patients, serial 24 hour Holter monitor recordings showed efficacy of treatment, defined as a 75% decrease in ventricular premature complexes, a 95% decrease in ventricular couplets and absence of ventricular tachycardia. During a mean followup period of 14.2 ± 9.9 months, 34 (32%) of the 107 patients had recurrence of a sustained ventricular tachyarrhythmia. Holter recording correctly predicted nine recurrences and correctly identified 37 patients who did not experience a recurrence. Holter efficacy failed to predict recurrence of a sustained ventricular tachyarrhythmia in 16 patients, and 18 patients remained free of recurrence despite failure to achieve Holter efficacy. The positive predictive value of Holter monitoring efficacy was 33% and the negative predictive value was 70%; however, these differences were not statistically significant by chi-square analysis. Similar results were obtained using Holter recordings performed relatively early in therapy (6 weeks and 4 months).Of the 27 patients without significant ventricular ectopic activity on the baseline Holter recording, 9 had an arrhythmia recurrence despite continued infrequent ventricular premature complexes and no repetitive forms on subsequent recordings. The recurrence rate in this group (33%) was similar to the overall recurrence rate.Therefore, among patients taking amiodarone for sustained ventricular tachyarrhythmias: 1) 25% will have insufficient ventricular ectopic activity on 24 hour Holter recordings for serial statistical analysis; and 2) in the remaining 75%, data obtained from serial Holter recordings are not predictive of arrhythmia recurrence

Acromegaly incidentally diagnosed at term in a pregnant woman presenting with ventricular premature complexes

Pituitary adenomas lead to increased growth hormone production and acromegaly. Pregnancy in acromegaly is rare as spontaneous conception is affected. We presented a case of 31 year old lady conceived by ovulation induction and presented at term gestation with ventricular premature complexes and was subsequently diagnosed with pituitary micro adenoma causing acromegaly. There has been no reported case of pregnancy with acromegaly presenting with premature ventricular complexes. Moreover, diagnosis of acromegaly in pregnancy is difficult and limited literature is available on its effects as well as management

A study of serum sodium and potassium levels in subjects of acute myocardial infarction in a tertiary care hospital in Eastern India

Background: Cardiovascular disease is one of the most common causes of morbidity and mortality around the world. In countries like India, there is difference in the lifestyle and behavioural risk factors among different areas. There is existence of rural-urban, Eastern-Western-Northern-Southern zonal differences. Studies done in other parts of India may not completely be applicable to Eastern Indian population. Serum electrolytes play an important role in maintaining electrophysiological homeostasis of the myocardial membrane, and alterations of these electrolyte levels can affect the pathogenesis, complications of myocardial infarction. Major serum electrolytes affecting the myocardial electrophysiological properties are sodium, potassium. Hence, this study was undertaken keeping in mind the miniscule lacunae in current knowledge especially pertaining to diseases in Eastern Indian population.Methods: 50 consecutive patients in the age group of 30-70 years admitted in the medicine department of Burdwan medical college with recent onset acute chest pain, diagnosed to be acute myocardial infarction were taken, their serum sodium, potassium levels were determined and these levels were compared among these patients with and without risk factors.Results: Serum sodium was decreased among patients with history of smoking, hypertension, BMI ≥25, complicated by atrial fibrillations. Serum potassium was decreased in patients with hypertension, BMI ≥25, ventricular premature complexes and increased in smokers, alcoholics.Conclusions: Electrolyte imbalances are common in patients of Acute Myocardial Infarction. Hypokalemia and hyponatremia were present and they were associated with cardiac complications. They adversely affect prognosis, so should be corrected

Arrhythmic risk in elderly patients candidates to transcatheter aortic valve replacement. predicative role of repolarization temporal dispersion

Degenerative aortic valve stenosis (AS) is associated to ventricular arrhythmias and sudden cardiac death, as well as mental stress in specific patients. In such a context, substrate, autonomic imbalance as well as repolarization dispersion abnormalities play an undoubted role. Aim of the study was to evaluate the increase of premature ventricular contractions (PVC) and complex ventricular arrhythmias during mental stress in elderly patients candidate to the transcatheter aortic valve replacement (TAVR). In eighty-one elderly patients with AS we calculated several short-period RRand QT-derived variables at rest, during controlled breathing and during mild mental stress, the latter being represented by a mini-mental state evaluation (MMSE). All the myocardial repolarization dispersion markers worsened during mental stress (p &lt; 0.05). Furthermore, during MMSE, low frequency component of the RR variability increased significantly both as absolute power (LFRR) and normalized units (LFRRNU) (p &lt; 0.05) as well as the low-high frequency ratio (LFRR/HFRR) (p &lt; 0.05). Eventually, twenty-four (30%) and twelve (15%) patients increased significantly PVC and, respectively, complex ventricular arrhythmias during the MMSE administration. At multivariate logistic regression analysis, the standard deviation of QTend (QTesd), obtained at rest, was predictive of increased PVC (odd ratio: 1.54, 95% CI 1.14–2.08; p = 0.005) and complex ventricular arrhythmias (odd ratio: 2.31, 95% CI 1.40–3.83; p = 0.001) during MMSE. The QTesd showed the widest sensitive-specificity area under the curve for the increase of PVC (AUC: 0.699, 95% CI: 0.576–0.822, p &lt; 0.05) and complex ventricular arrhythmias (AUC: 0.801, 95% CI: 0.648–0.954, p &lt; 0.05). In elderly with AS ventricular arrhythmias worsened during a simple cognitive assessment, this events being a possible further burden on the outcome of TAVR. QTesd might be useful to identify those patients with the highest risk of ventricular arrhythmias. Whether the TAVR could led to a QTesd reduction and, hence, to a reductionof thearrhythmicburdenin thissettingofpatients isworthytobe investigated

Twenty-four Hour Holter Monitoring in Finishing Cattle Housed Outdoors

Ambulatory electrocardiogram monitoring, in the form of Holter monitoring, has been used in human and veterinary medicine for decades as an aid in the diagnosis and determination of appropriate therapy of heart rhythm disturbances. Within veterinary medicine, Holter monitors have been primarily used in companion animal species, yet little attention has been given to food animal species. Moreover, the heart rhythm in clinically normal cattle fed high concentrate diets and housed outdoors in confined drylot facilities has not been previously reported. In order to properly identify pathologic arrhythmias in cattle, the normal rhythm and arrhythmia prevalence in healthy cattle should be defined. Most prior reports of arrhythmia in cattle have been recordings of relatively shorter duration and in animals that were hospitalized or being handled for various reasons. Therefore, the objective of this study was to determine normal Holter monitor registrations including heart rate, rhythm, number of ventricular premature complexes, and atrial premature complexes in unrestrained finishing Angus steers

T. brucei cathepsin-L increases arrhythmogenic sarcoplasmic reticulum-mediated calcium release in rat cardiomyocytes

Aims: African trypanosomiasis, caused by Trypanosoma brucei species, leads to both neurological and cardiac dysfunction and can be fatal if untreated. While the neurological-related pathogenesis is well studied, the cardiac pathogenesis remains unknown. The current study exposed isolated ventricular cardiomyocytes and adult rat hearts to T. brucei to test whether trypanosomes can alter cardiac function independent of a systemic inflammatory/immune response. Methods and results: Using confocal imaging, T. brucei and T. brucei culture media (supernatant) caused an increased frequency of arrhythmogenic spontaneous diastolic sarcoplasmic reticulum (SR)-mediated Ca2+ release (Ca2+ waves) in isolated adult rat ventricular cardiomyocytes. Studies utilising inhibitors, recombinant protein and RNAi all demonstrated that this altered SR function was due to T. brucei cathepsin-L (TbCatL). Separate experiments revealed that TbCatL induced a 10–15% increase of SERCA activity but reduced SR Ca2+ content, suggesting a concomitant increased SR-mediated Ca2+ leak. This conclusion was supported by data demonstrating that TbCatL increased Ca2+ wave frequency. These effects were abolished by autocamtide-2-related inhibitory peptide, highlighting a role for CaMKII in the TbCatL action on SR function. Isolated Langendorff perfused whole heart experiments confirmed that supernatant caused an increased number of arrhythmic events. Conclusion: These data demonstrate for the first time that African trypanosomes alter cardiac function independent of a systemic immune response, via a mechanism involving extracellular cathepsin-L-mediated changes in SR function