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Background Magnetic resonance imaging (MRI) in patients with cardiac pacing devices has become available despite previously being considered absolutely contraindicated. However, most institutional safety protocols have included several limitations on patient selection, leaving MRI unavailable for many patients. Purpose To evaluate the first 1000 MRI examinations conducted on patients with cardiac pacing devices at Helsinki University Hospital for any potential safety hazards and also to evaluate the long-term functionality of the safety protocol in "real-life" clinical practice. Material and Methods A total of 1000 clinically indicated MRI scans were performed with a 1.5-T MRI scanner according to the safety protocol. The following information was collected from the electronic medical record (EMR): patients' date of birth; sex; pacing device generator model; date of MRI scan; date of the latest pacing device generator implantation; and the body region scanned. The EMR of these patients was checked and especially searched for any pacing device related safety hazards or adverse outcomes during or after the MRI scan. Results Only one potentially dangerous adverse event was noted in our study group. In addition, patients with abandoned leads, temporary pacing devices, and newly implanted pacing device generators were scanned successfully and safely. Conclusion MRI scans can be performed safely in patients with cardiac pacing devices if the dedicated safety protocol is followed.

Background Paroxysmal atrial fibrillation (pAF) is a major risk factor for ischemic stroke, but challenging to detect with routine short-term monitoring methods. In this pilot study, we present a novel method for prolonged ECG and screening for pAF in patients with a recent embolic stroke of unknown source (ESUS). Methods Fifteen patients aged ≥ 50 years with a recent ESUS were assigned to wear an external electrode belt-based 1-lead ECG device (Beat2Phone) continuously for 2 weeks (wear time). The device was operated via a mobile phone application in nonhospital conditions. The primary outcome was patient adherence to monitoring. Secondary outcomes were incidence of new pAF, quality-wise comparison to Holter, and usability of the novel ECG monitoring method with Systems Usability Scale (SUS). We also performed a 24- to 48-hr comparison between simultaneous Beat2Phone ECG and a standard Holter in 6 patients. Results Wear time of Beat2Phone device was over 80% in 5 (33.3%) patients, 50%-80% in 7 (46.6%) patients, and less than 50% in 3 (20%) patients. We detected pAF ≥ 30 s in 1 patient (6.7%). In the simultaneous monitoring with Beat2Phone and Holter, there were a total of 817 (out of 1979) analyzable periods of sinus rhythm or premature atrial or ventricular beats (Cohen's Kappa coefficient 0.92 ± 0.02 between Beat2Phone and Holter), and no pAF events. Beat2Phone ECG showed remarkable SUS scores in user evaluations (average score: 81.4 out of 100 on SUS). Conclusions Beat2Phone device was easy to use among ESUS patients and in optimal conditions provided high-quality 1-lead ECG signal for diagnosing pAF. Clinical trial registration The study was not registered, as it was a nonrandomized single-arm pilot study.

Various lead designs have been developed to accommodate different coronary sinus anatomies. Our objectives were to compare electrical parameters of straight and spiral left ventricular leads, to evaluate capture thresholds and impedances using different pacing vectors, and to study evolution of thresholds over time.The RALLY-X4 study enrolled patients implanted with a lead from the Acuity X4 family (straight, spiral short, or spiral long). Electrical parameters (including capture thresholds from all 17 vectors) were measured at baseline and follow-up.Data from 795 patients who were successfully implanted were analyzed. Straight and spiral leads had similar proportions of patients with thresholds2.5 V/0.4 ms using the distal electrode (61-65% of patients) or from at least one of the proximal (E2-E4) electrodes (81-83% of patients). Unipolar vectors had significantly lower thresholds and impedances than bipolar vectors, with similar measurements compared to extended bipolar configurations. Capture thresholds increased with more proximal electrodes for all leads. Over a mean follow-up of 1 year, a slight decrease in capture thresholds was observed.Straight and spiral quadripolar leads allow to obtain clinically acceptable capture thresholds from at least one of the proximal electrodes in80% of patients. Pacing vectors significantly affect electrical parameters, with higher thresholds in more proximal electrodes and lower thresholds with unipolar and extended bipolar configurations. Capture thresholds slightly decreased over a mean follow-up of 1 year.

Infections after placement of cardiac implantable electronic devices (CIEDs) are associated with substantial morbidity and mortality. There is limited evidence on prophylactic strategies, other than the use of preoperative antibiotics, to prevent such infections.We conducted a randomized, controlled clinical trial to assess the safety and efficacy of an absorbable, antibiotic-eluting envelope in reducing the incidence of infection associated with CIED implantations. Patients who were undergoing a CIED pocket revision, generator replacement, or system upgrade or an initial implantation of a cardiac resynchronization therapy defibrillator were randomly assigned, in a 1:1 ratio, to receive the envelope or not. Standard-of-care strategies to prevent infection were used in all patients. The primary end point was infection resulting in system extraction or revision, long-term antibiotic therapy with infection recurrence, or death, within 12 months after the CIED implantation procedure. The secondary end point for safety was procedure-related or system-related complications within 12 months.A total of 6983 patients underwent randomization: 3495 to the envelope group and 3488 to the control group. The primary end point occurred in 25 patients in the envelope group and 42 patients in the control group (12-month Kaplan-Meier estimated event rate, 0.7% and 1.2%, respectively; hazard ratio, 0.60; 95% confidence interval [CI], 0.36 to 0.98; P = 0.04). The safety end point occurred in 201 patients in the envelope group and 236 patients in the control group (12-month Kaplan-Meier estimated event rate, 6.0% and 6.9%, respectively; hazard ratio, 0.87; 95% CI, 0.72 to 1.06; P0.001 for noninferiority). The mean (±SD) duration of follow-up was 20.7±8.5 months. Major CIED-related infections through the entire follow-up period occurred in 32 patients in the envelope group and 51 patients in the control group (hazard ratio, 0.63; 95% CI, 0.40 to 0.98).Adjunctive use of an antibacterial envelope resulted in a significantly lower incidence of major CIED infections than standard-of-care infection-prevention strategies alone, without a higher incidence of complications. (Funded by Medtronic; WRAP-IT ClinicalTrials.gov number, NCT02277990.).

Background Atrial fibrillation (AF) frequently escapes routine stroke workup due to its unpredictable and often asymptomatic nature, leaving a significant portion of patients at high risk of recurrent stroke. Recent trials emphasized continuous electrocardiogram (ECG) monitoring in the detection of occult AF. We screened AF in patients meeting the embolic stroke of unknown source (ESUS) criteria using an external miniaturized recorder with an adhesive electrode. Methods Patients aged ≥50 with recent ESUS were prospectively screened and assigned to wear a 1‐lead ECG device capable to record continuous ECG for up to 4 weeks. Electrodes were replaced every 3–4 days. Primary outcome was proportion of patients completing at least 80% of monitoring. Secondary outcome measures included incidence of AF and initiation of oral anticoagulation therapy after AF detection. Results Fifty‐seven patients were monitored (mean age 64.5 ± 8.2 years, median delay from stroke to the start of monitoring 8 days, IQR 4–44). Of these, 51 patients (89.5%) completed at least 80% of the desired monitoring period. We detected AF ≥30 s in seven patients (12.3%), all of whom initiated anticoagulation therapy. Atrial fibrillation was revealed in six patients (85.7%) within the first week of monitoring. Compared to patients without AF, patients with AF were older (70.6 ± 5.1 vs. 63.6 ± 8.3 years, p

Undetermined strokes with an embolic pattern (USEP) represent a common phenotype. We assessed their frequency and compared USEP with cardioembolic stroke with a known source and non-cardioembolic stroke etiology.Study patients were 540 consecutive ischemic stroke patients admitted to Helsinki University Hospital with primary end-point of recurrent stroke in a 21-month follow-up. Cox regression adjusting for CHA2DS2-VASc and anticoagulation estimated the risk of USEP on recurrent stroke.A total of 229 (42.4%) patients had a non-cardioembolic stroke etiology, 184 (34.1%) had a cardioembolic stroke with a known source, and 127 (23.5%) were classified as USEP. USEP patients had less diabetes and prior TIA, with more severe symptoms than the non-cardioembolic stroke cases. They were younger, had fewer comorbidities, and less severe symptoms than the cardioembolic stroke patients. Cumulative risk of recurrent stroke was 10.0% (95% CI 4.1%-15.9%) for USEP, 5.0% (1.1%-8.9%) for cardioembolic strokes, and 5.0% (3.0%-7.0%) for non- cardioembolic strokes (P = 0.089). USEP associated with a higher risk of recurrent stroke compared to non-cardioembolic strokes (hazard ratio 2.36, 95% CI 1.02-5.47; P = 0.046) and cardioembolic stroke with a known source (1.83, 1.07-3.14; P = 0.028).Despite their younger age and more favorable risk factor profile compared with other phenotypes, USEP exhibited a high risk of stroke recurrence.

Background Magnetic resonance imaging (MRI) of pacemaker patients has become available despite of previous contraindications. However, pacing systems containing ferromagnetic material may hamper the diagnostic quality of cardiac MR (CMR) images. Purpose To study methods for reducing susceptibility-based artifacts in CMR examinations of pacemaker patients. Material and Methods Altogether 16 patients were scanned with 1.5T MRI scanner using cine balanced steady-state free-precession (bSSFP) and spoiled gradient echo (SPGR) sequences. The use of frequency-scout was also evaluated. For myocardial late gadolinium-enhanced (LGE) imaging, SPGR or bSSFP readout inversion-recovery prepared gradient echo sequences were used with and without phase-sensitive inversion-recovery (PSIR). Two radiologists subjectively compared the image quality (IQ) and the ranges of susceptibility artifacts were evaluated objectively. Results The IQ proved adequate for diagnosing each patient, although in a few patients with a left-side implanted generator, artifacts hampered IQ in the anterior and anteroseptal segments of the myocardium in bSSFP cine and LGE sequences. In bSSFP cine, the use of frequency-scout could often transfer the banding artifacts away from the left ventricular myocardium. In LGE imaging, the artifacts were more pronounced in IR-bSSFP and PSIR than in IR-SPGR sequences. The ranges of generator-based artifacts were greater in bSSFP (10–12 cm) than in SPGR (6 cm) sequences due to banding artifacts. Conclusion The artifacts caused by pacemakers typically did not compromise the diagnostic IQ. The use of frequency-scout prior to bSSFP cine or the use of SPGR-based sequences could also improve IQ.

AIMS: The aim of this study was to investigate the prognosis in patients with atrial fibrillation (AF) and intracerebral hemorrhage (ICH) having a left atrial appendage occlusion (LAAO) versus patients receiving standard medical therapy.METHODS AND RESULTS: A total of 151 patients from the Nordic countries with AF and previous ICH who underwent LAAO using the Amplatzer Cardiac Plug or the Amplatzer Amulet were compared to a propensity score matched group of 151 patients receiving standard medical therapy. The two groups were matched so that their risks for stroke and bleeding were similar (CHA2DS2VASc and HASBLED scores). The standard care patients were identified from the Danish Stroke Registry among 787 patients with AF and ICH. The primary endpoint was a composite of all-cause mortality, ischemic stroke and major bleeding. Patients with AF and a prior ICH treated with LAAO had a lower risk of the composite outcome as compared to patients treated with standard medical care (events/1000 years [95% confidence interval]: 53.3 [44.3-64.1] vs. 366.7 [298.2-450.9]; Hazard Ratio 0.16 [0.07-0.37].CONCLUSIONS: LAAO is suggested to be of major clinical benefit in AF patients having sustained an ICH. These results have to be confirmed in a randomized clinical trial.

Objectives The aim of this study was to introduce a single centre “real life” experience of performing MRI examinations in clinical practice on patients with cardiac pacemaker systems. Additionally, we aimed to evaluate the safety of using a dedicated safety protocol for these patients. Materials and methods We used a 1.5 T MRI scanner to conduct 68 MRI scans of different body regions in patients with pacing systems. Of the cardiac devices, 32% were MR-conditional, whereas the remaining 68% were MR-unsafe. We recorded the functional parameters of the devices prior, immediately after, and approximately one month after the MRI scanning, and compared the device parameters to the baseline values. Results All MRI examinations were completed safely, and each device could be interrogated normally following the MRI. We observed no changes in the programmed parameters of the devices. For most of the participants, the distributions of the immediate and one-month changes in the device parameters were within 20% of the baseline values, although some changes approached clinically important thresholds. Furthermore, we observed no differences in the variable changes between MR-conditional and MR-unsafe pacing systems, or between scans of the thorax area and other scanned areas. Conclusion MRI in patients with MR-conditional pacing systems and selected MR-unsafe systems could be performed safely under strict conditions in this study.

The aim of the study was to evaluate the performance of pacemakers (PM) atrial tachyarrhythmia (AT)-sensing algorithms in sinus node dysfunction (SND) patients with DDDR pacing programmed with a fixed long atrioventricular (AV) delay.In a prospective study, a total of 60 patients with SND were implanted with a dual-chamber PM with two different algorithms for detection of ATs. The study was done with a 3 month data collection period retrieved from the memory of PM and with a 7 day external Holter recording period.In 13 of 16 (81 %) patients whose Holter recording revealed the presence of ATs, episodes of AT sensing were retrieved from the PM memory with electrograms verifications, confirming that the devices had detected the ATs. Very short ATs seen in Holter recordings were missed by the PM with three patients. However, with all these patients after 3 months of follow up period, there were recognized periods of ATs by the PM. With ten (17 %) patients, there were intermittent periods of undersensing by the PM although continuous atrial fibrillation (AF) was seen in the Holter recording. Retrograde conduction caused false AT detection due to repetitive non-reentrant ventriculoatrial synchronous rhythm (RNRVAS) in six (25 %) of the 24 patients with retrograde conduction.Even with long AV delay, ATs can be accurately identified. However, transient undersensing of continuous AF and non-detection of very short AT episodes can still occur. Programming a long AV delay predisposes to RNRVAS which can cause false AT detection and symptoms in SND patients who have retrograde conduction.

In atrial fibrillation (AF), warfarin prevents ischemic strokes (IS), but its implementation varies. We conducted a retrospective registry study on clinical features and prior warfarin therapy in AF patients with IS. Of our 540 patients, 143 had a prior diagnosis of AF, of which 51% used warfarin. Warfarin use was more common in those having permanent than paroxysmal AF (76% versus 36%, p0.001). On admission, 42% had INR within the therapeutic range. Average TTR was 64%. Advanced age (p=0.009) and permanent AF (p0.001) were associated with higher TTR. Better warfarin therapy quality was associated with advanced age and permanent AF.

Owing to potential serious safety risks, magnetic resonance imagings of patients having cardiac pacemakers have long been forbidden. Due to the increased demand, modes of operation have, however, been developed for safe imaging, taking the benefit-risk aspects into account. The mode of operation devised in collaboration between the HUCH Cardiology Outpatient Clinic and the radiology unit of the HUS Medical Imaging and Physiology makes safe magnetic resonance imagings possible without body area restrictions for all kinds of cardiac pacemaker patients. By using the developed mode of operation, imaging of 268 patients with cardiac pacemakers have already been carried out safely by the end of October 2014. We describe the content of the mode of operation and the current status of the investigations, with a brief look into the future.

To investigate if an advanced AV search hysteresis (AVSH) algorithm, Ventricular Intrinsic Preference (VIP(™)), reduces the incidence of ventricular pacing (VP) in sinus node dysfunction (SND) with both intact and compromised AV conduction and with intermittent AV block regardless of the lead positions in the right atria and the ventricle.Patients were classified as having intact AV (AVi) conduction if the PR interval was ≤ 210 ms on ECG and 1:1 AV conduction during atrial pacing up to 120 bpm with PR interval ≤ 350 ms. Otherwise the AV conduction was classified as compromised (AVc). Both AVi and AVc patients were randomized to VIP ON or OFF. VIP performed an intrinsic AV conduction search every 30 s for three consecutive atrial cycles with the extension of the sensed and paced AV (SAV/PAV) delays from basic values of 150/200 ms to 300/350 ms. Extended AV intervals were allowed for three cycles when VP occurred before returning to basic AV delays. The primary end-point was %VP at 12 months.Among 389 patients, 30.1% had intact and 69.9% had compromised AV conduction. The mean %VP at 12 months was 9.6% by VIP compared to 51.8% with standard AV settings in patients with AVi (P0.0001) and 28.0% versus 78.9% (P0.0001) with AVc. With VIP, excessive %VP among most used lead positions was not seen. Conversely, when VIP was off %VP was low only in patients who had leads in the RA septal-RV septal position (23.0%).VIP feature reduces VP both in patients with SND and with intermittent heart block regardless of the lead positions in the right atria and the ventricle.

The main objective of this study was to characterize morphological differences between sinus and retrograde atrial waves. We collected intracardiac atrial signals through a DDDR pacemaker to characterize their morphologies and discriminate retrograde from sinus atrial waves off-line. Intracardiac unipolar and bipolar signals were collected at an 800-Hz sampling rate through a 0.4-Hz high-pass filter. Sinus and retrograde atrial waves during ventricular pacing were recorded in the supine and upright positions. Eleven different form parameters (FPs) were applied to describe atrial wave morphology. Data from 14 patients were collected and analyzed. Atrial signals differed markedly between the two body postures. However, it was possible to discriminate retrograde from sinus atrial waves on the basis of at least one FP in 12 of 14 (86%) patients when unipolar and bipolar atrial signals recorded in both body postures were analyzed separately. When body postures were pooled together to mimic natural conditions, discrimination was successful in nine of 14 patients with either configuration of the atrial signal. The results indicate that retrograde atrial waves can be discriminated from sinus waves by using high sampling rate, digital signal processing, and specific FPs incorporated in these pacemakers.

Aims The aim of this study was to evaluate the current short-term (80% of all complications. The complication rate was more than twice as high in bradycardia pacemaker (PM) implantations performed by cardiology trainees (17.4%) than by experienced cardiologists (7.7%, P = 0.001). When performed by experienced cardiologists, the complication rate was not higher in implantations of more complex devices compared with that of bradycardia PMs. Fifty-two of the 69 patients needed additional surgical procedures. Altogether, the complications required 504 additional treatment days in hospital. Conclusion In conclusion, our retrospective 1-year single-centre survey shows that short-term implantation-related complications of contemporary device therapy are still frequent, occur much more frequently by trainees than by cardiologists, require a large number of additional surgical procedures, and substantially prolong the hospital stay.