Sacubitril/Valsartanstive Heart Failure: Cardiogenic Shock.

Sacubitril/valsartan is a combination drug described as a new class of dual-acting angiotensin receptor-neprilysin inhibitor (ARNi) for heart failure. We present a case of a patient with NYHA class IV systolic heart failure who was refractory to all other classes of heart failure medications and was started on this new medication. On sacubitril/valsartan, he developed cardiogenic shock. This led us to reevaluate the use and risks of this medication in the class IV heart failure population.

Arrhythmia issues in patients with renal disease.

Arrhythmia issues arise frequently in the renal disease population, spanning the spectrum from benign ectopy to sustained arrhythmias. Studies adding to our understanding of arrhythmias and advances in technology have revolutionized the way we deal with many arrhythmias. In dealing with ventricular tachyarrhythmias, risk stratification is important, class III antiarrhythmics are preferred medications, and implantable defibrillators have assumed a dominant role. Atrial fibrillation, the most common cardiac arrhythmia, presents the challenges of dosing and drug interactions in the renal disease population; established and evolving catheter ablation approaches are becoming increasingly important. Other supraventricular arrhythmias will occur in this population and will require management. Permanent pacemakers continue to have a significant role for bradyarrhythmias; newer modes and features allow tailoring of these devices to individual patients. In addition, newer types of pacemakers may allow for clinical improvement in heart failure patients. Appropriate handling of arrhythmias can enhance the survival and quality of life of patients with renal disease.

Right atrial mapping and linear ablation for paroxysmal atrial fibrillation.

OBJECTIVE: Catheter ablation techniques to cure atrial fibrillation (AF) are under investigation. This study evaluates a mapping-based, individualized approach to right atrial (RA) linear ablation in patients with paroxysmal AF. METHODS: In this prospective observational study, 29 patients with recurrent symptomatic AF refractory to medical therapy, underwent linear ablation between May 1998 and December 1999. Inclusion criteria were symptomatic paroxysmal AF, failure of at least 2 antiarrhythmic medications, and informed consent. Radiofrequency ablation was performed in the RA using a 3.3 French multielectrode catheter, ablating through sequential electrodes to establish linear lesions. Lesions were delivered during sustained AF, guided by an empiric mapping scheme, targeting arrhythmogenic areas noted during electrophysiologic testing in sinus rhythm and areas of most disorganization during AF. Reinduction of AF was attempted at the end of successful ablation. RESULTS: The mean age was 58 years. There were 15 male and 14 female patients. Sustained AF was inducible in all patients at electrophysiology study. Acute success was achieved in 24 patients (83%). Long term success (maintaining sinus rhythm off antiarrhythmic medications) was seen in 23 (79%) over a mean follow-up of 19.7 months. Ablation lines varied from patient to patient. There were no complications. CONCLUSIONS: Individualized linear ablation in the RA using a multielectrode catheter system can produce effective suppression of paroxysmal AF. Ablation during AF, and testing to reinduce AF at the end of the procedure, make this study unique.

Long QTc and torsades de pointes in human immunodeficiency virus disease.

Three patients with human immunodeficiency virus (HIV) infection presented with QT, prolongation (> 440 ms) and torsades de pointes. We sought to evaluate the etiology of the long QT syndrome in these patients without previously identified causes for QT, prolongation, and determine the prevalence among patients with HIV infection. The three index patients underwent: (1) left stellate ganglion block; (2) beta-blocker challenge; and (3) electrocardiographic stress testing. QTc interval was measured before and after intervention. We undertook a retrospective analysis of prevalence of QTC prolongation among all patients with computerized ECGs over a 6-month period at one institution and compared it to the prevalence in hospitalized patients with HIV disease. Thirty-four thousand one hundred eighty-one patients with computerized ECGs were screened for QTc prolongation. Forty-two hospitalized patients with HI disease had computerized ECG during the same 6-month period. In the three index patients, the QTc failed to shorten with left stellate ganglion blockade, beta-blocker challenge, or stress testing, suggesting an acquired form of the long QT syndrome in these patients with HIV disease. None had previously recognized acquired causes of QT, prolongation. Mexiletine hydrochloride was useful in preventing recurrences of torsades de pointes. We observed a 7.0% prevalence of QT, prolongation among all patients screened. Hospitalized patients with HIV disease (n = 42) during this same period, demonstrated an increased prevalence of QT, prolongation (28.6%, P = 0.002). Patients with HIV disease have a significantly higher prevalence of QTc prolongation than a general hospital-based population, may have an unrecognized acquired form of the long QT syndrome, and are at risk for torsades de pointes.

Radiofrequency ablation of an accessory pathway in a patient with corrected Ebstein's anomaly.

Ebstein's anomaly of the tricuspid valve has a known association with the Wolff-Parkinson-White syndrome. Radiofrequency ablation has become the treatment of choice for the latter, but there have been no reports of the feasibility of this procedure after tricuspid valve replacement. We present a patient who first exhibited evidence of intermittent preexcitation and associated symptomatic arrhythmia 9 years after tricuspid valve replacement for Ebstein's anomaly, and describe the challenges posed by this case.

Intraatrial conduction delay associated with an epicardial implantable cardioverter-defibrillator.

The implantable cardioverter-defibrillator (ICD) has become an important mode of therapy for patients at risk for sustained ventricular arrhythmias. While the survival benefit of these devices is clear, adverse consequences are coming to light. The authors report a case of dramatic intraatrial conduction delay associated with repeated ICD shocks, resulting in pacemaker syndrome in a patient who had received both an ICD and a dual-chamber pacemaker. This and other conduction disturbances may become more common as experience with ICDs grows, and may demand adjunctive or alternative therapies to prevent frequent shocks.

Case report: pentamidine and polymorphic ventricular tachycardia revisited.

Pentamidine isethionate has been associated with ventricular tachyarrhythmias, including torsade de pointes. This article reports two cases of this complication and reviews all reported cases to date. Pentamidine-induced torsade de pointes may be related to serum magnesium levels and hypomagnesemia may synergistically induce torsade. Torsade de pointes occurred after an average of 10 days of treatment with pentamidine. In these patients, no other acute side effects of pentamidine were observed. Torsade de pointes can be treated when recognized early, possibly without discontinuation of pentamidine. When QTc interval prolongation is observed, early magnesium supplementation is advocated.

Cardiovascular changes in pregnancy evaluated by two-dimensional and Doppler echocardiography.

During pregnancy significant cardiovascular changes occur. To study these anatomic and physiologic changes we performed two-dimensional and Doppler echocardiography in 28 women during the third trimester (34.4 +/- 1.9 weeks) of pregnancy and then again after delivery (7.8 +/- 2.2 weeks). Fourteen nonpregnant age- and sex-matched subjects served as controls. Left ventricular diastolic and systolic dimensions were similar among pregnant, postpartum, and control subjects. Left atrial area as determined by two-dimensional echocardiography was significantly larger during pregnancy (16.7 +/- 4.0 cm2) compared with measurements postpartum (13.8 +/- 3.1 cm2) and with controls (15.5 +/- 3.5 cm2) (p less than 0.01). Doppler study showed that the ratio of early diastolic flow velocity to late diastolic flow velocity (E/A max) and E/A integral were lower among pregnant subjects (1.3 +/- 0.3, 2.0 +/- 0.5) compared with postpartum subjects (1.6 +/- 0.4, 2.5 +/- 1.5) and controls (1.9 +/- 0.5, 3.0 +/- 0.8) (p less than 0.05). Heart rate was higher among pregnant subjects (84 +/- 10 beats/min) compared with postpartum subjects (70 +/- 16) and controls (69 +/- 13) (p less than 0.05). In summary, in pregnant subjects during late third trimester left ventricular chamber dimensions were similar to these postpartum measurements in control subjects; however, the left atrium is dilated during pregnancy. Although there are significant alterations in Doppler-derived left ventricular diastolic parameters during the third trimester, increased heart rate and a dilated left atrium may explain these findings.

Pneumococcal pericarditis successfully treated with catheter drainage and intravenous antibiotics.

Bacterial pericarditis is commonly a disease of children for which the primary treatment is surgical drainage. We report the case of a 19-yr-old patient presenting with pneumococcal pericarditis and tamponade treated successfully with intrapericardial catheter drainage and intravenous antibiotics. The technical aspects are discussed.