Pepa Sanchez-Borque

Long‐Term Outcomes of Ivabradine in Inappropriate Sinus Tachycardia Patients: Appropriate Efficacy or Inappropriate Patients

Inappropriate sinus tachycardia (IST) is characterized by persistent and disproportional elevation of heart rate (HR). Ivabradine has been successfully used in some patients.

Silent ischaemic brain lesions related to atrial high rate episodes in patients with cardiac implantable electronic devices

AIMS Monitoring capabilities of cardiac implantable electronic devices have revealed that a large proportion of patients present silent atrial fibrillation (AF) detected as atrial high rate episodes (AHREs). Atrial high rate episodes >5 min have been linked to increased risk of clinical stroke, but a high proportion of ischaemic brain lesions (IBLs) could be subclinical. METHODS AND RESULTS We prospectively analysed the incidence of AHRE > 5 min in 109 patients (56% men, aged 74 ± 9 years) and the presence of silent IBL on computed tomography (CT) scan. Mean CHADS2 and CHA2DS2VASc scores were 2.3 ± 1.3 and 3.9 ± 1.6, respectively. Seventy-five patients (69%) had no history of AF or stroke/transient ischaemic attack (TIA). After 12 months, 28 patients (25.7%) showed at least one AHRE. Patients with AHREs were more likely to have history of AF. Computed tomography scan showed silent IBL in 28 (25.7%). The presence of IBL was significantly related to older patients, prior history of AF or stroke/TIA, higher CHADS2 or CHA2DS2VASc scores, and the presence of AHRE. Multivariable analysis demonstrated that AHRE was an independent predictor for silent IBL in overall population [hazard ratio (HR) 3.05 (1.06-8.81; P < 0.05)] but also in patients without prior history of AF or stroke/TIA [HR 9.76 (1.76-54.07; P < 0.05)]. CONCLUSION Cardiac implantable electronic devices can accurately detect AF as AHRE. Atrial high rate episodes were associated to a higher incidence of silent IBL on CT scan. Atrial high rate episodes represent a kind of silent AF where management recommendations are lacking despite the fact that a higher embolic risk is present.

Silent brain infarcts in high blood pressure patients with cardiac implantable electronic devices: unmasking silent atrial fibrillation.

Background: Hypertensive patients present a higher risk for developing atrial fibrillation and its complications. Cardiac implantable electronic devices (CIEDs) have shown reliable atrial fibrillation detection as atrial high-rate episodes (AHREs). The presence of AHRE more than 5 min has been related to increased risk of stroke, but a high proportion of ischemic brain lesions (IBLs) could be subclinical and thromboembolic risk underestimated. Methods: We included hypertensive patients with CIED and we analyzed the incidence of AHRE and the presence of IBL on computed tomography (CT) scan. Results: One hundred and twenty-three patients (57% men) aged 77 ± 8 years were evaluated during a mean follow-up of 15 ± 9 months. AHREs were documented in 46 patients (37%). Cranial CT scan showed silent IBL in 34 patients (27%). Univariate analysis showed that age, CHADS2 and CHADS2VA2Sc scores, history of prior stroke/ transient ischemic attack and the presence of AHRE were significantly related to higher risk for IBL on CT scan (P < 0.05). Multivariate analysis showed that the presence of AHRE more than 5 min [odds ratio 3.05 (1.19–7.81; P < 0.05)] was an independent predictor of IBL. Conclusion: Silent atrial fibrillation detected by CIED as AHRE is really prevalent in hypertensive patients. AHREs were independently associated with a higher incidence of silent IBL on CT scan.

CorVue algorithm efficacy to predict heart failure in real life: Unnecessary and potentially misleading information?

Heart failure (HF) hospitalizations have a negative impact on quality of life and imply important costs. Intrathoracic impedance (ITI) variations detected by cardiac devices have been hypothesized to predict HF hospitalizations. Although Optivol™ algorithm (Medtronic, Minneapolis, MN, USA) has been widely studied, CorVue™ algorithms (St. Jude Medical, St. Paul, MN, USA) long‐term efficacy has not been systematically evaluated in a “real‐life” cohort.

Ineffective appropriate shocks in coronary artery spasm disease: when defibrillation is not enough

A 50-year-old woman without relevant medical history or risk factors received a single-chamber Fortify Assura (St Jude Medical) implantable cardioverter defibrillator (ICD) after recovering from sudden cardiac death (SCD). No structural heart disease was documented and coronary angiogram performed showed normal coronary arteries. Submuscular left-sided ICD implantation with dual-coil electrode was performed without incidences, defibrillation test was not performed. ICD was programmed in VVI 40 bpm for bradycardia and two zones for tachycardia settings (170–200 bpm monitor and > 200 bpm with maximum energy shocks: 36J+40Jx5, RV to SVC&can, biphasic, tilt 65%/65%, 5.6 ms). The patient was discharged and some weeks later was readmitted after syncope. ICD was interrogated showing a ventricular fibrillation (VF) episode that is correctly detected and treated with appropriate ICD shocks. Stored intracardiac electrograms showed ineffective shocks at maximum energy (Fig. 1a). ICD parameters were in the normal limits. Defibrillation test was performed showing successful VF defibrillation at low energy shocks (Fig. 1b). Telemetry ECG monitoring during admission showed a progressive ST elevation coincidental with chest discomfort and palpitations (Fig. 2) compatible with nonpreviously diagnosed coronary artery spasm (CAS). The episode was sustained developing polymorphic ventricular tachycardias and VF which were correctly detected by the ICD (Fig. 3). However, high-energy appropriate shocks applied were ineffective restoring sinus rhythm. In fact, sinus rhythm was restored spontaneously and ST segment normalized some minutes later. The patient started high doses of calcium channel blockers (diltiazem 120 mg/8 h) and remains without recurrences after over 3 years of follow-up. CAS is a more common cause of SCD than previously expected in patients with absence of coronary artery disease [1]. Recurrent episodes and ventricular arrhythmias may be prevented if CAS can be effectively addressed with risk factor modification and ongoing treatment with nitrates and calcium channel blockers. Patients with lifethreatening ventricular tachyarrhythmias secondary to CAS are at particularly high-risk for recurrence. In spite of medical intervention or if compliance is poor, 6% of patients suffered new events in the long-term. ICD implantation could be considered in secondary prevention [2]. Unfortunately, ICD therapies might not be efficient to prevent SCD in the setting of new prolonged ischemic episodes and during the subsequent reperfusion phase. The efficacy of ICD therapy may be hampered throughout refractory severe ischemia [3]. As shown in Fig. 1, successful low-energy shocks during defibrillation test at normal conditions does not imply the same efficacy during ischemic conditions. This fact highlights the importance of aggressive medical therapy directed against CAS in addition to ICD implantation in these patients. In our case, the patient was untreated because she received the ICD before being diagnosed of CAS. Further studies are needed to evaluate the role of ICD in CAS patients under optimal treatment. * Juan Benezet-Mazuecos jbenezet@fjd.es

Inappropriate automatic mode switching episodes: What's the mechanism?

We present a case series of five patients reporting abnormal automatic mode switching (AMS) episodes during routinary cardiac defibrillator (ICD) and pacemaker (PM) follow-up. This non-previously described phenomenon was reported to St. Jude Medical (Abbott) Technical Support that confirmed the inappropriate automatic mode switching.

Ictal asystole: A condition between neurology and cardiology

Ictal asystole can appear in patients with focal epilepsy, even in early phases. We present our experience of 7 cases, remarking the electrocardiographic characteristics, the role of apnea, treatment and long-term evolution. Awareness of this entity and collaboration between neurologists and cardiologists are essential for a correct diagnosis and management.

Silent atrial fibrillation in pacemaker early post-implantation period: an unintentionally provoked situation?

Aims Atrial high-rate episodes (AHREs) compatible with silent AF detected in pacemakers (PM) are related to an increased risk of stroke and silent ischaemic brain lesions (IBL) on CT scan. AHREs soon after PM implantation could be related with the procedure itself and the prognosis might be different. Methods and results We analysed the incidence of AHREs >5 min and the presence of silent IBL in 110 patients (56% men, aged 75 ± 9 year-old) with PM and no history of AF, in relation to time from implantation (≤3 months vs. >3 months) and the atrial lead fixation (LF) (active vs. passive). Mean CHADS2 and CHA2DS2VASc scores were 1.9 ± 1.2 and 3.5 ± 1.5, respectively. Time from implantation was ≤3 months in 88 patients (80%). Active LF was used in 55 patients (50%). After 24 ± 9 months, AHREs were present in 40 patients (36.4%). CT-scan showed silent IBL in 26 patients (23.6%). The presence of AHREs at 3 months was more frequent in the patients with recent PM implantation (17% vs. 4.5%, P = 0.09) and significantly related to active LF (OR 5.36, 1.43-20.07; P < 0.05). The presence of silent IBL was related to the detection of AHREs during follow up (OR 3.12, 1.29-7.97; P < 0.05) but not with AHREs at first 3 months (OR 1.58, 0.49-5.05; P = 0.44). Conclusions AHREs occur frequently during the first 3 months after PM implantation and could be related with procedure itself and the use of active LF. AHREs in this period might not be related to worse outcomes and should be interpreted cautiously.

Cardiac Arrest With ST-Segment–Elevation in V1 and V2: Differential Diagnosis

A 58-year-old male patient arrived at the emergency department following out-of-hospital cardiac arrest. He had no known cardiovascular risk factors other than smoking. His relatives reported that he had developed oppressive retrosternal chest pain and sweating 3 hours prior to presentation. The first documented rhythm was ventricular fibrillation, requiring 4 electric shocks to restore sinus rhythm and return of spontaneous circulation. The postresuscitation ECG is shown in Figure 1. What is the most likely diagnosis? Figure 1. The 12-lead ECG at the emergency room. The 12-lead ECG at the emergency room, showing ST-segment–elevation in lead V1 and V2. Please turn the page to read the diagnosis. The ECG revealed sinus rhythm, narrow QRS complex, ST-segment–elevation in lead V1 and V2, with a slight elevation in leads III and aVF and 1-mm ST-segment–depression in leads I and aVL. Surprisingly, no pathological Q waves were evidenced after more than 3 hours of chest pain. These …

ATRIAL HIGH RATE EPISODES AND SILENT ISCHEMIC BRAIN LESIONS IN PATIENTS WITH CARDIAC IMPLANTABLE ELECTRONIC DEVICES: UNMASKING SILENT ATRIAL FIBRILLATION EMBOLIC RISK

Cardiac implantable electronic devices (CIED) reveal that many patients present silent atrial fibrillation (AF) detected as atrial high rate episodes (AHRE). AHRE >5min have been linked to increased risk of clinical stroke, but a high proportion of ischemic brain lesions (IBL) could be subclinical