Malini Madhavan

Stress hormone and circulating biomarker profile of apical ballooning syndrome (Takotsubo cardiomyopathy): insights into the clinical significance of B-type natriuretic peptide and troponin levels

Objective: To evaluate the stress neurohumoral and cardiac biomarker profile of patients with apical ballooning syndrome (ABS). Methods: Plasma-free metanephrines, B-type natriuretic peptide (BNP), high sensitivity C-reactive protein (hsCRP) and troponin T, as well as 24-hour urine catecholamines, metanephrines and free cortisol were measured in 19 ABS and 10 ST-elevation myocardial infarction (STEMI) patients. Results: An antecedent stressful event was identified in 15 ABS patients. There were no differences in plasma normetanephrine (median 0.64 (IQ range 0.43–0.97) nmol/l vs 0.53 (0.32–0.77) nmol/l, pu200a=u200a0.44), metanephrine (0.10 (0.10–0.22) nmol/l vs 0.16 (0.10–0.38) nmol/l, pu200a=u200a0.29), or cortisol levels (16.0 (7.3–44.0) μg/dl vs 13.0 (10.5–23.5) μg/dl, pu200a=u200a0.95) between ABS and STEMI patients. The 24-hour urine metanephrines, catecholamines and cortisol levels were normal in the majority of ABS patients. Troponin T levels were lower (0.62 (0.18–0.84) ng/ml vs 3.80 (2.04–6.57) ng/ml, p<0.001), but BNP levels were higher in ABS compared with STEMI (944 (650–2022) pg/ml vs 206 (140–669) pg/ml, pu200a=u200a0.009). HsCRP was similarly elevated in the two groups (11.0 (5.1–110.8) mg/l and 24.3 (8.1–88.6) mg/l, pu200a=u200a0.78). Conclusions: Catecholamine and cortisol levels were not elevated in our cohort of ABS, suggesting that routine measurement of these stress hormones is unlikely to be of diagnostic value in practice. In contrast to STEMI, ABS is characterised by a greater elevation in BNP and less myonecrosis.

Acute heart failure in apical ballooning syndrome (TakoTsubo/stress cardiomyopathy): clinical correlates and Mayo Clinic risk score.

To the Editor: nnApical ballooning syndrome (ABS) is an acute cardiac syndrome characterized by transient regional systolic dysfunction of the left ventricle (LV) in the absence of obstructive coronary artery disease ([1][1]). Systolic heart failure (HF) is the most common complication and merits

Brain natriuretic peptide in apical ballooning syndrome (Takotsubo/stress cardiomyopathy): comparison with acute myocardial infarction.

ObjectivesApical ballooning syndrome (ABS) is a transient cause of ventricular dysfunction. The aim of this study was to determine the clinical and hemodynamic correlates of brain natriuretic peptide (BNP) levels in ABS and compare the biomarker profiles in ABS with acute myocardial infarction controls. MethodsFifty-seven prospectively diagnosed patients with ABS whose BNP and troponin T level measurements were available were included. Fifty patients with ST-elevation myocardial infarction (STEMI) and 25 individuals with non-ST-elevation myocardial infarction (NSTEMI) were included as matched controls. ResultsIn the ABS cohort, the BNP levels were higher in patients older than 65 years compared with younger individuals: 767 (269, 951) versus 340 (131, 904.5), P=0.019. There were no significant correlations between BNP levels and hemodynamic parameters such as left ventricular ejection fraction and end diastolic pressure. There were no correlations between BNP and peak troponin T (r=0.03, P=0.8). BNP levels were significantly higher in ABS patients when compared with the STEMI and NSTEMI controls. The BNP to peak troponin T ratio was significantly higher in ABS compared with the STEMI controls 1089.4 (446.7, 3334.8) versus 97.4 (17.9, 264.7), P=0.04. ConclusionBNP elevation is almost universal in ABS. Cardiac hemodynamic indices do not correlate with BNP levels. The magnitude of BNP elevation is higher in ABS compared with STEMI and NSTEMI.

Cardiac sympathetic activity in stress-induced (Takotsubo) cardiomyopathy

Background. A 54-year-old postmenopausal woman presented with retrosternal chest pressure, nausea, and vomiting of 4 h duration. Her medical history included hypertension (treated with metoprolol and ramipril), hyperlipidemia (treated with atorvastatin), and depression (treated with fluoxetine). A few hours before symptom onset, she had witnessed an accident in which her sister sustained serious injuries. The patient was visiting her sister—who was in critical condition in the hospital—when the symptoms began.Investigations. Physical examination, chest radiography, laboratory testing, electrocardiography, coronary angiography, and PET with 11C hydroxyephedrine.Diagnosis. Stress-induced (Takotsubo) cardiomyopathy (apical ballooning syndrome).Management. The patient was monitored with cardiac telemetry. Metoprolol and ramipril were continued.

Electrogram guidance: a method to increase the precision and diagnostic yield of endomyocardial biopsy for suspected cardiac sarcoidosis and myocarditis.

OBJECTIVESnThe aim of this study was to describe the method used to perform electrogram-guided EMB and correlatexa0electrogram characteristics with pathological and clinical outcomes.nnnBACKGROUNDnEndomyocardial biopsy (EMB) is valuable in determining the underlying etiology of a cardiomyopathy. The sensitivity, however, for focal disorders, such as lymphocytic myocarditis and cardiac sarcoidosis (CS), is low. Thexa0sensitivity of routine fluoroscopically guided EMB is low. Abnormal intracardiac electrograms are seen at sites ofxa0myocardial disease. However, the exact value of electrogram-guided EMB is unknown.nnnMETHODSnWe report 11 patients who underwent electrogram-guided EMB for evaluation of myocarditis and CS.nnnRESULTSnOf 40 total biopsy specimens taken from 11 patients, 19 had electrogram voltagexa0<5 mV, all of which resulted in histopathologic abnormality (100% specificity and positive predictive value). A voltage amplitude cutoff value of 5 mV had substantially higher sensitivity (70% vs. 26%) and negative predictive value (62%) than 1.5 mV. Abnormal electrogram appearance at biopsy site had good sensitivity (67%) and specificity (92%) in predicting abnormal myocardium. Normal signals with voltage >5 mV signified normal myocardium with no significant diagnostic yield. Biopsy results guided therapy in all patients, including 5 with active myocarditis or CS, all of whom subsequently received immunosuppressive therapy. There were no procedural complications.nnnCONCLUSIONSnIn patients with suspected myocarditis or CS, electrogram-guided EMB targeting sites with abnormal orxa0low-amplitude electrograms may increase the diagnostic yield for detecting abnormal pathological findings.

Optimal Programming of Implantable Cardiac-Defibrillators

Implantable cardioverter-defibrillators (ICDs) reduce sudden cardiac death risk and improve survival in patients with a history of life-threatening arrhythmia or cardiac arrest (secondary prevention) and in high-risk patients without such a history (primary prevention).1–3 Patients with ICDs, however, may receive unnecessary shocks, which have been associated with proarrhythmia, anxiety, depression, poor quality of life, and possibly increased mortality.4–8 In contrast to drug therapy, in which a limited number of parameters (such as dose) are adjustable, hundreds of programmable parameters affect device therapy delivery. Moreover, selection of nonnominal parameter settings (ie, changing the out-of-the-box factory default settings) reduces morbidity and mortality compared with nominal settings in many clinical situations because of publication and regulatory delays.4,9,10 Thus, optimization of programming to prevent unnecessary shocks is paramount to minimize morbidity and mortality and is dependent on clinician proactivity.nnDelivery of ICD therapy for rhythms other than ventricular tachycardia (VT) or ventricular fibrillation (VF) is termed inappropriate therapy . It may result from inappropriate detection of supraventricular tachycardia (SVT) such as atrial fibrillation (AF) or sinus tachycardia or from oversensing of physiological (eg, T wave) or nonphysiological (eg, lead fracture noise) signals. Inappropriate shocks have been reported in 16% to 18% of ICD recipients and constitute 30% to 50% of all shocks.11–13 Although therapy delivered for a ventricular tachyarrhythmia is considered appropriate, a growing body of evidence has shown that programming antitachycardia pacing (ATP) or delaying shocks to permit nonsustained episodes to terminate significantly reduces the frequency of shock delivery. Koneru et al14 have used the term unnecessary shocks to refer to inappropriate shocks delivered for rhythms other than VT/VF and to include shocks delivered for VT that would have responded to ATP or terminated spontaneously if given time. Optimal programming minimizes unnecessary shocks.nnA …

Risk of stroke after catheter ablation versus cardioversion for atrial fibrillation: A propensity-matched study of 24,244 patients.

BACKGROUNDnStroke is the major cause of morbidity and mortality related to atrial fibrillation (AF). Catheter ablation for AF is effective in reducing AF burden, but its impact on long-term stroke risk is unknown.nnnOBJECTIVEnWe sought to evaluate the periprocedural and long-term stroke risk after catheter ablation or cardioversion for AF.nnnMETHODSnThis retrospective, propensity-matched study using a national administrative claims database identified patients with AF who underwent catheter ablation and a comparison group (matched on age, sex, year of treatment, CHA2DS2-Vasc score, and Charlson index) who underwent cardioversion between 2005 and 2012. The primary end points were (1) time to first ischemic or hemorrhagic stroke or transient ischemic attack (TIA) and (2) time to first ischemic or hemorrhagic stroke excluding TIA. We compared periprocedural incident stroke (within 30 days of ablation or cardioversion) as well as total strokes between the 2 groups.nnnRESULTSnA total of 24,244 patients (12,122 patients undergoing ablation and 12,122 patients undergoing cardioversion) were included in the analysis. Incident periprocedural stroke or TIA occurred in 0.5% of the ablation group and 0.3% of the cardioversion group (P = .04). There was a significant initial risk of stroke/TIA with ablation within the first 30 days (rate ratio 1.53; P = .05). After 30 days, this risk was significantly lower in the ablation group (rate ratio 0.78; P = .03).nnnCONCLUSIONnIn patients with AF, there is a small periprocedural stroke risk with ablation in comparison to cardioversion. However, over longer-term follow-up, ablation is associated with a slightly lower rate of stroke.

Outcomes in Patients With Cardiovascular Implantable Electronic Devices and Bacteremia Caused by Gram-Positive Cocci Other Than Staphylococcus Aureus

Background—Infection is a serious complication of cardiovascular implantable electronic device (CIED) placement and requires device removal for attempted cure. Methods and Results—We studied the rate, risk factors, and outcomes of CIED infection in 74 consecutive patients with bacteremia caused by Gram-positive cocci (GPC) other than Staphylococcus aureus between 2001 and 2007. CIED infection was defined as the presence of signs of infection at the generator site, lead vegetations seen on echocardiography, or microbiological growth from device cultures. Twenty-two (30%) of 74 patients with non–S aureus GPC bacteremia had CIED infections. Coagulase-negative staphylococci (CoNS) accounted for 73% of CIED infections. The rate of CIED infection in patients with CoNS bacteremia was almost 2-fold that of non-CoNS GPC bacteremia (36% versus 20%, P=0.13). The number of leads, the presence of abandoned leads, and prior generator replacement were associated with CIED infection. Among 33 patients without identifiable CIED infection at initial evaluation who did not undergo device removal, 5 (15%) had relapsing bacteremia within 12 weeks of completing antibiotic therapy. CoNS accounted for all relapses, and none had evidence of CIED infection at relapse. Conclusions—Patients with a CIED and bacteremia caused by GPC other than S aureus frequently had evidence of underlying CIED infection on clinical evaluation that included transesophageal echocardiography. This was particularly true among those with CoNS bacteremia. No evidence of underlying CIED infections was identified in the subgroup of patients who did not have manifestations of CIED infection on initial evaluation but subsequently had relapsing bacteremia caused by CoNS.

Outcomes in Patients with Cardiovascular Implantable Electronic Devices and Bacteremia Due to Gram-Positive Cocci Other Than Staphylococcus aureus

Background—Infection is a serious complication of cardiovascular implantable electronic device (CIED) placement and requires device removal for attempted cure. Methods and Results—We studied the rate, risk factors, and outcomes of CIED infection in 74 consecutive patients with bacteremia caused by Gram-positive cocci (GPC) other than Staphylococcus aureus between 2001 and 2007. CIED infection was defined as the presence of signs of infection at the generator site, lead vegetations seen on echocardiography, or microbiological growth from device cultures. Twenty-two (30%) of 74 patients with non–S aureus GPC bacteremia had CIED infections. Coagulase-negative staphylococci (CoNS) accounted for 73% of CIED infections. The rate of CIED infection in patients with CoNS bacteremia was almost 2-fold that of non-CoNS GPC bacteremia (36% versus 20%, P=0.13). The number of leads, the presence of abandoned leads, and prior generator replacement were associated with CIED infection. Among 33 patients without identifiable CIED infection at initial evaluation who did not undergo device removal, 5 (15%) had relapsing bacteremia within 12 weeks of completing antibiotic therapy. CoNS accounted for all relapses, and none had evidence of CIED infection at relapse. Conclusions—Patients with a CIED and bacteremia caused by GPC other than S aureus frequently had evidence of underlying CIED infection on clinical evaluation that included transesophageal echocardiography. This was particularly true among those with CoNS bacteremia. No evidence of underlying CIED infections was identified in the subgroup of patients who did not have manifestations of CIED infection on initial evaluation but subsequently had relapsing bacteremia caused by CoNS.

Cardiac Pacemakers: Function, Troubleshooting, and Management: Part 1 of a 2-Part Series

Advances in cardiac surgery toward the mid-20th century created a need for an artificial means of stimulating the heartxa0muscle. Initially developed as large external devices, technological advances resulted in miniaturization of electronic circuitry and eventually the development of totally implantable devices. These advances continue to date, withxa0the recent introduction of leadless pacemakers. In this first part of a 2-part review, we describe indications, implant-related complications, basic function/programming, common pacemaker-related issues, and remote monitoring,xa0which are relevant to the practicing cardiologist. We provide an overview of magnetic resonance imaging andxa0perioperative management among patients with cardiac pacemakers.