Hemodynamics of His Bundle Pacing.

In addition to the His bundle, numerous other sites have been evaluated as more physiologic alternatives to pacing at the right ventricular apex. Several hemodynamic studies have shown the benefit of His bundle pacing and septal pacing in comparison with right ventricular apical pacing. This article summarizes this literature and presents acute hemodynamic data in an intrapatient study examining His bundle pacing, right ventricular septal pacing, and right ventricular apical pacing.

Figure-of-eight suture for venous hemostasis in fully anticoagulated patients after atrial fibrillation catheter ablation.

INTRODUCTION: Limited data exists for types of venous closure and its associated complications in patients after atrial fibrillation (AF) catheter ablation. We evaluated the subcutaneous figure-of-eight closure (FO8) for achieving venous hemostasis after AF catheter ablation compared to manual pressure. METHODS: 284 consecutive patients that underwent AF catheter ablation by two operators were included. All patients received continuous therapeutic warfarin or interrupted novel oral anticoagulants (NOAC) and heparin (ACT300-400 s) without reversal. Patients were divided into two groups: 1) sheaths were left in place and pulled once ACT < 180 s, with hemostasis being achieved with manual pressure (MP); and 2) a subcutaneous FO8 suture closed the venous access site immediately after the ablation on each groin site and sheaths were removed immediately after the ablation despite full anticoagulation with heparin and warfarin or interrupted NOAC. Sutures were removed after four hours, and the patients laid flat for an additional two hours. RESULTS: The MP group (n = 105) was similar to the FO8 group (n = 179). Time in bed was 573 ± 80 min for MP group vs. 373 ± 49 min for FO8 group (p < 0.0001). Eleven hematomas were seen in the MP group compared to seven in the FO8 group (P = 0.041). CONCLUSIONS: In fully anticoagulated patients undergoing AF catheter ablation, excellent hemostasis was achieved with figure-of-eight sutures, with no major vascular complications, a lower hematoma rate, and a significantly shorter flat-time-in-bed compared to manual pressure.

Incidence of Pocket Infection Postcardiac Device Implantation Using Antibiotic versus Saline Solution for Pocket Irrigation.

BACKGROUND: Preprocedure systemic antibiotic prophylaxis reduces infections in patients undergoing cardiac implantable electronic devices (CIEDs) implantations. Whether pocket irrigation with antibiotic solution offers any advantage over saline solution in CIED implantation is unknown. METHODS: Records from 327 consecutive patients who underwent CIED implantation by three operators from February 2011 to January 2014 were reviewed. From February 2011 to January 2012, the antibiotic solution was used for pocket irrigation; from February 2012 to January 2014, saline solution was used. All patients received preprocedural IV antibiotics. Baseline demographics, comorbidities, lab data, and occurrence of any pocket infection postimplant were collected. RESULTS: There were 118 and 209 patients in the antibiotic solution and saline solution group, respectively. A total of four (1.2%) patients had CIED infection: two in the antibiotic solution group and two in the saline solution group. Median time to infection from implant date was 81.5 ± 35 days. Two patients (50%) had infection after first device implantation. Of the four patients, one had positive blood culture, three had positive pocket cultures, one had lead vegetation, one underwent pocket exploration, and all of them had devices/leads extracted, with reimplantation on the contralateral side. No mortality was observed due to infectious complications. CONCLUSION: When compared to pocket irrigation in the antibiotic solution group, the saline solution group was not associated with increased incidence of infectious complications after CIED implantation. The use of saline solution pocket irrigation alone may be used in CIED pocket irrigation periprocedurally.  Further evaluation in larger randomized trials is needed.

Syncope: Approaches to Diagnosis and Management.

Syncope is defined as a transient loss of consciousness due to cerebral hypoperfusion followed by spontaneous recovery. Common causes of syncope include vasovagal syncope, situational syncope, orthostatic hypotension, carotid sinus hypersensitivity, left- and right-sided obstructive cardiac lesions, and cardiac arrhythmias. History and physical examination often provide valuable clues about the underlying etiology of syncope. Admission decisions in the emergency department can be guided by various risk prediction scores. Evaluation of a patient with syncope involves a large battery of diagnostic tests that include a 12-lead electrocardiogram, Holter monitoring, echocardiogram, tilt table testing, ischemia evaluation, electrophysiologic studies, and other imaging tests. Despite the availability of these advanced diagnostic tests, a significant proportion of patients with syncope remain undiagnosed. Therapy should be tailored based on the underlying etiology of syncope.

Have we given up on intra-aortic balloon counterpulsation in post-myocardial infarction cardiogenic shock?

The recently published Intra-aortic Balloon Pump in Cardiogenic Shock II (IABP-SHOCK II) trial concluded that intra-aortic counterpulsation (IACP) does not reduce 30-day mortality in patients with cardiogenic shock (CS) complicating acute myocardial infarction (AMI) for whom early revascularization strategy was planned. The study resulted in downgrading IACP in post-AMI CS patients by certain professional organizations like the European Society of Cardiology. Although this is the largest and most important CS study of this decade, it suffers from considerable shortcomings: (1) time intervals from chest-pain onset or AMI recognition to revascularization, enrollment, and IACP initiation are not disclosed; (2) 86.6% of the treatment arm initiated IACP only post-percutaneous coronary intervention (PCI), and 4.3 % did not receive IACP at all; (3) 17.4% of the control arm crossed over to IACP or other mechanical support, mostly due to protocol violations; (4) there is no adjudication of the mortality events; (5) follow-up is limited to 30 days; and (5) both methodology (especially IACP device size) and quality of IACP are not evaluated and documented. Because the study assessed mostly the efficacy and safety of IACP initiated post-PCI, the study conclusions should not be extrapolated to IACP pre-PCI or during PCI in CS. Moreover, IACP had a favorable effect on the mortality of younger patients. Intra-aortic counterpulsation should remain the first line of mechanical circulatory support for the hemodynamically compromised AMI patients with or without CS who are undergoing primary PCI. Early upgrade to more advanced mechanical circulatory support should be considered for selective suitable candidates who remain in refractory CS despite revascularization and IACP.

Use of antiplatelet agents in patients with atherosclerotic disease.

Platelets play a key role in the initiation of hemostatic mechanisms during vascular injury. When contemplating prescription of antiplatelet agents (APAs) for patients as primary prevention for cardiovascular events, the physician should carefully weigh the potential benefits of cardiovascular risk reduction with the likelihood of harm, related mostly to hemorrhagic complications. The role of APAs in secondary prevention of atherosclerosis and coronary artery disease is well established, however, optimal duration of therapy and intensity of patient treatment are not settled and probably need to be individualized per patient. We describe the data emerging from contemporary trials on the efficacy and safety of the use of oral APAs in various patient subpopulations. We also discuss the advantages and potential roles of new APAs during and following acute coronary syndromes, percutaneous coronary interventions, and symptomatic atherosclerosis. We propose certain strategies and directions for future research to enhance the safety and efficacy prevention by optimizing the beneficial effects of APAs along with other contemporary treatment modalities of primary and secondary prevention.

Artefactual spikes in electrocardiography: a worthwhile introspection.

Electrical devices, which have become an integral part of our daily life, may influence the electrical recording of the heart. These disturbances from external sources outside of the heart's own activity produce changes in the electrocardiography (ECG) of the patient, simulating rhythmic disturbances of the heart. Understanding these disturbances is essential in order to better interprete the ECG. Common sources of electrical interferences include external devices, such as alternating current and improper earthing, and surgical procedures like diathermy. We report a case of electrical interference in a patient's ECG due to an inserted bladder stimulator. This case report highlights the importance of precise identification of artefacts in the interpretation of ECG, as well as prompt localisation and elimination of the source of interference.

Riata lead failure with normal electrical lead parameters and normal fluoroscopic appearance.

Recently, insulation breach of the Riata lead raised a big concern. Management of these externalized leads has been addressed by professional organizations. However, what to do in patients with Riata leads without manifested failure is an ongoing clinical dilemma. Here, we present two clinical scenarios where the implantable cardioverter defibrillator system failed to deliver shock therapy in spite of having a new ICD generator and "appropriately functioning leads" as revealed by lead interrogation.

Incidence of amiodarone hypersensitivity in patients with previous allergy to iodine or iodinated contrast agents.

STUDY OBJECTIVE: To determine the incidence and nature of allergic reactions to amiodarone in hospitalized patients with a listed allergy to iodine or iodinated radiocontrast agents. DESIGN: Retrospective medical record review. SETTING: Two academic medical centers. PATIENTS: A total of 234 sequential hospitalized patients with a listed iodine and/or iodinated radiocontrast agent allergy who received oral or intravenous amiodarone between January 2006 and December 2010. MEASUREMENTS AND MAIN RESULTS: Demographic and clinical data, as well as documentation of an allergic reaction to amiodarone, were collected for each patient from electronic medical records. Mean ± SD age was 69 ± 12 years, and 51% were male. Of the 234 patients, 167 (71%) had a listed previous allergy to iodinated contrast agents, 55 (24%) to iodine, and 12 (5%) to both. Patients received an average inpatient total dose of 2.9 ± 3.2 g of either oral (106 patients [45%]), intravenous (39 patients [17%]), or both oral and intravenous (89 patients [38%]) amiodarone. Only 1 (0.4%) of the 234 patients was identified as having a probable allergic reaction to amiodarone (score of 6 on the Naranjo adverse drug reaction probability scale). One additional patient receiving intravenous amiodarone experienced a rash that was determined to be caused by an antibiotic. All other patients received amiodarone without any identifiable allergic reactions. CONCLUSION: The incidence of hypersensitivity reaction to amiodarone in hospitalized patients with a listed allergy to iodine or iodinated contrast agents was less than 1%, and all identified reactions were without long-term sequelae. Allergy to iodine and iodinated contrast agents may not be a valid absolute contraindication to amiodarone administration in the inpatient setting.

Externalized Conductor Cables in QuickSite Left Ventricular Pacing Lead and Riata Right Ventricular Lead in a Single Patient: A Common Problem With Silicone Insulation.

QuickSite (St Jude Medical, Sylmar, CA, USA) is a silicone and polyurethane-insulated coronary sinus pacing lead. Riata lead (St Jude Medical, Sylmar, CA, USA) is a silicone insulated right ventricular shock lead. Recently, insulation breach of silicone based leads raised a huge concern. Fluoroscopic examination of these two leads in the same patient revealed externalization of these two leads. Same mechanism producing insulation breach of Riata lead may be involved in externalization of QuickSite LV lead as distal part of insulation is also made of silicone.

All That Glitters is not Gold: Apical Hypertrophic Cardiomyopathy Mimicking Acute Coronary Syndrome.

Hypertrophic cardiomyopathy is characterized by the idiopathic hypertrophy of the left ventricle (and occasionally right ventricle). HCM is an autosomal dominant disease, with variable penetration. In Asian population, apical hypertrophic cardiomyopathy is relatively common (25%). However, this is relatively rare in Caucasian population (0.2%). Patients with HCM, often presents with typical exertional chest pain and shortness of breath. Apical HCM patients tend to have milder symptoms. However, the clinical presentation and electrocardiographic features of Apical HCM often mimic acute coronary syndrome and high index of suspicion is warranted in differentiating this condition. Patients with apical HCM have relatively better prognosis when compare to the other varieties. Here, we are presenting a patient who presented with typical exertional chest pain whose electrocardiographic changes are concerning for acute ischemic changes.

Corrected QT interval as a predictor of mortality in elderly patients with syncope.

BACKGROUND: Prolonged corrected QT interval (QTc) holds independent prognostic importance in predicting mortality in patients with coronary artery disease, diabetes mellitus and congestive heart failure. However, its association with all cause or cardiac mortality in the general population remains unclear. We evaluated the relationship between prolonged QTc and total mortality among patients with syncope. METHODS: This was a retrospective study of 348 patients presenting to the emergency department with syncope of any etiology over a period of one year. All patients with atrial fibrillation, left bundle branch block and cardiac devices (pacemaker/defibrillator) were excluded. Prolonged QTc interval was defined as QTc interval ≥ 440 ms. The primary end point for this study was total mortality in patients presenting with syncope. RESULTS: There were 58 (16%) deaths in this population during a mean follow-up of 30 months. Patients with prolonged QTc interval had significantly higher mortality when compared to those with normal QTc interval (22% vs 11%; p = 0.004). This significance was not retained after adjustment for covariates in the Cox regression model, where we found that age ≥ 65 years (hazard ratio [HR] 7.9; 95% confidence interval [CI] 1.9-32.9; p = 0.004) and QTc interval ≥ 500 ms (HR 3.5; 95% CI 1.56-8.12; p = 0.002) were predictors of increased mortality among patients with syncope. CONCLUSIONS: In elderly patients presenting to the emergency department with syncope, QTc interval ≥ 500 ms helps identify patients at higher risk of adverse outcomes.

Migration of the chest tube into the esophagus in a case of Boerhaave's syndrome.

Boerhaave's syndrome is the spontaneous transmural rupture of the esophagus. Patients can have a variety of manifestations. Boerhaave's syndrome has to be considered in acutely ill patients with no other explanations for their illness. Computed tomography scan of the chest is emerging as a useful tool for the evaluation of these patients. Surgical repair is the standard of care. Adequate drainage of the pleural fluid is necessary to prevent pulmonary complications. Esophageal perforation should be considered whenever thoracostomy tube drainage assumes an enteric character. When inserting the chest tube for draining pleural fluid, the trochar should not be used because of potential injury to the already perforated esophagus. Posterior placement of the chest tube should be avoided because the tube may migrate into the perforated esophagus. Because of the high incidence of mortality, prompt suspicion, diagnosis, and management are warranted. A careful history, detailed review of the imaging, and a high index of suspicion are key for prompt diagnosis.

Underutilization of Implantable Cardioverter Defibrillator in Primary Prevention of Sudden Cardiac Arrest.

BACKGROUND: The aim of this study was to evaluate the overall use of implantable cardioverter defibrillators (ICD) for primary prevention of sudden cardiac arrest (SCA), among eligible patients from an outpatient cardiology clinic and to determine what factors might contribute to underutilization of ICDs. METHODS: This report was a retrospective chart review of patients with ischemic or non-ischemic cardiomyopathy and left ventricular ejection fraction ≤ 35% from an outpatient cardiology practice from January 2005 to May 2008. These patients met the eligibility criteria for ICD implantation for primary prevention of SCA. A detailed review of medical records captured distribution of ICD implantation including future plans for ICD implant, patient preference against ICD use, presence of severe co-morbidities, and any other documented reasons/contraindications regarding ICD implantation. RESULTS: Of the 275 patients who were eligible for ICD for primary prevention of SCA, 119 (43%) had an ICD implantation. ICDs were used in 84 (48%) eligible men and 35 (35%) eligible women (P 0.02). Among 156 (57%) patients who did not receive ICD, 79 (28%) had severe co-morbidities precluding them from having ICD. Twenty-six patients (10%) refused to have ICD implanted. The remaining 51 (19%) patient charts did not include any documentation regarding ICD use (future plan or contraindication). CONCLUSIONS: ICDs are underutilized for primary prevention of SCA, with rates of use being lowest among eligible women. This underutilization exists even after accounting for patient preferences and presence of severe co-morbid conditions that might make an otherwise eligible patient not a suitable candidate for ICD implantation.

Right Ventricle Failure in Sepsis: A Case Report.

Sepsis could produce myocardial depression and typically it affects the left ventricle (LV). Sepsis could also affect right ventricle (RV), in addition to the interdependence with LV. RV pressure may be elevated secondary to pulmonary vasoconstriction, leading to RV dysfunction. Unlike LV, RV is poorly prepared to compensate for acute overload. Aggressive volume replacement may be vital to maintain RV function, but excess hydration can cause RV dilation, decreased LV diastolic filling, and reduced cardiac output. In patients having signs of inadequate cardiac output even after initial volume resuscitation, RV function should be assessed with echocardiogram. If RV dysfunction is noted, then fluid therapy should be guided by CVP measurements. If cardiac output increases with increasing CVP, maintaining higher filling pressures on the right side is indicated. On the other hand, increasing CVP with worsening of the cardiac output could worsen the RV dysfunction. In addition to the fluid management, treatment of other reversible causes like acidosis and hypoxia is also a key.

The broken pen penalty.

Insulin pen devices have revolutionized the self-management of diabetes. Prefilled insulin pens are preferred by healthcare providers and patients because of ease-of-use, dosage flexibility, disposability, and widespread availability. However, like any mechanical device, these pens have the potential for mechanical malfunction. We are present a case in which glycemic control deteriorated because of a malfunction of an insulin pen. The possibility of insulin pen malfunction needs to be considered in addition to other factors in patients who present with acute deterioration of glycemic control.

Sucrose Nephropathy Following IV Immunoglobulin.

Treatment with Intravenous Immunoglobulin (IVIg) has been found to be useful in patients with variety of diseases. IVIg infusions can produce allergic reactions. These adverse reactions are thought to be caused by activation of the complement cascade by the aggregation of IgG. To avoid this, a variety of stabilizing agents, including sucrose, are used. Sucrose is metabolized in the intestines by sucrase. If sucrose is given intravenously, this will be reabsorbed in to the proximal convoluted tubule and produce osmotic nephropathy which will present clinically as oliguric acute kidney injury. Patients with preexisting renal insufficiency, diabetes mellitus, elderly (>65 years), volume depletion and sepsis are more prone for these adverse effects and care should be taken not to use the IVIg with sucrose as a stabilizer in this population. If no other options are available, reductions in dose, concentration, and/or rate of administration of IVIg are warranted to reduce the incidence of renal failure. Pharmacist should be aware of the clinical scenario of the patient and choose the IVIg with appropriate stabilizer.

Direct His bundle pacing post AVN ablation.

Atrioventricular nodal (AVN) ablation with concomitant pacemaker implantation is one of the strategies that reduce symptoms in patients with atrial fibrillation (AF). However, the long-term adverse effects of right ventricular (RV) apical pacing have led to the search for alternating sites of pacing. Biventricular pacing produces a significant improvement in functional capacity over RV pacing in patients undergoing AVN ablation. Another alternative site for pacing is direct His bundle to reduce the adverse outcome of RV pacing. Here, we present a case of direct His bundle pacing using steerable lead delivery system in a patient with symptomatic paroxysmal AF with concurrent AVN ablation.

Permanent pacemaker implantation via left superior vena cava without communication with the coronary sinus.

The persistence of the left superior vena cava is a rare venous anomaly and usually does not produce hemodynamic disturbances. Left sided cardiac device implantation has increased the awareness of this rare anomaly. In most cases, left superior vena cava connects to the right heart via coronary sinus. We describe a rare case of successful permanent pacemaker implantation via left superior vena cava-accessory hemiazygos-hemiazygos-inferior vena caval communication.