Mechanical dyssynchrony, a novel marker to predict long-term survival in patients with cardiac resynchronization

Background

Cardiac resynchronization therapy (CRT) is an established therapy in patients with symptomatic heart failure with reduced left ventricular ejection fraction (LVEF <35%) (HFrEF) that have conduction disturbances as measured by prolonged QRS duration of >130 ms. Mechanical dyssynchrony (MD) in echocardiography has not proven benefit to determine CRT indication, but is hypothesized to be of predictive value. Both MD aspects of “apical rocking” (AR) but also “septal flash” (SF) have been shown to be a predictive value in short- and medium-term follow-up in CRT, but no trial has tested long-term effects yet.

Purpose

This study investigated the impact of AR and SF on long-term survival in CRT recipients.

Methods and results

425 HFrEF patients (mean age: 63.0±10.6 years, 72.3% male, 60.7% non-ischemic etiology) with ESC guideline-derived CRT indication have been implanted and additionally investigated for MD markers at baseline as well as after a 11.5±8.0 months follow-up including long-term survival. Herein AR and/or SF were identified in 307 (72,2%) participants at baseline. During follow-up both AR and/or SF disappeared in 256 (83.4%) patients through CRT use. The overall mean survival was 95.9±52.9 months. Univariable analysis showed beneficial survival for women over men (109.1±52.4 vs. 90.9±52.4 months; p<0.001). Moreover, younger (<60 years) patients profit more than older patients (110.6±53.7 vs. 88.6±51.1 months; p<0.001). Interestingly, patients with MD markers at baseline generally had an improved overall survival (106.2±52.0 vs. 68.9±45.4 months; p<0.001), and in addition to that we found the best survival in patients with disappeared over persisting mechanical dyssynchrony echocardiography parameters in CRT (111.6±51.2 vs. 79.7±47.6 months p<0.001). Multivariate analysis shows age and presence of MD at baseline to be powerful predictors for long-term survival in CRT HFrEF patients (Figures 1 and 2).

Conclusion

Novel echocardiography MD parameters before CRT implantation predict long-term survival. Moreover, long-term survival even further improves when AR and/or SF disappear through CRT in HFrEF. Our results encourage a prospective, randomized, controlled, multicenter trial to study clinical implementation of MD in CRT patients.

Funding Acknowledgement

Type of funding sources: None.

Repeat procedures and reconnection rates after cryoballoon PVI with phrenic nerve injury

Funding Acknowledgements

Type of funding sources: None.

Aims

Cryoballoon (CB) based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury which is leading to premature abortion of the freeze cycle. Here we analysed repeat procedures and reconnection rates after CB-based PVI and phrenic nerve injury in a large-scale population. Due to the fact that the freezing process was prematurely interrupted the data may offer unique findings in optimizing the CB dosing protocols.

Methods and Results

In the YETI registry a total of 17356 patients underwent CB-based PVI in 33 centers and 731 (4.2%) patients experienced phrenic nerve injury. A total of 111 / 731 (15.2%) patients received a repeat procedure utilizing a 3D mapping system due to AF recurrence. In 94/111 (84.7%) of patients data on repeat procedures was available. During their initial PVI procedures, phrenic nerve injury occurred during treatment of RSPV (n=80), RIPV (n=13) and LSPV (n=1). A total of 89/94 (94.7%) target PVs have been isolated during the initial PVI (RSPV: 75/80, 94%; RIPV: 13/13; 100%; LSPV: 1/1; 100%). The mean freezing time was 127±46s and the mean minimal temperature was -49±7°C. During the repeat procedures 67 of initially 89 isolated PVs showed persistent isolation (75%, for RSPV: 55/75; 73%; RIPV: 11/13; 85%; LSPV: 1/1; 100%).

Conclusion

In patients initially treated by CB-based PVI with interruption of the freezing due to phrenic nerve injury, a high rate of durable isolated PVs has been detected at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures

Fifty-fifty - a comparison of two 50 watts high power short duration protocols using temperature- versus power- controlled radiofrequency ablation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Radiofrequency-guided catheter ablation (RFCA) is an established treatment option for atrial fibrillation (AF). New approaches applying higher than usual energy levels for shorter periods (high power short duration, HPSD) to improve lesion quality have been reported. The novel DiamondTemp (DT) catheter allows for temperature-guided high power RFCA. Data on a direct comparison of the two emerging RFCA approaches are lacking.

Purpose

This observational single center study aimed to compare the efficacy, safety and characteristics of the novel DT catheter to an ablation index (AI) guided 50 W high power short duration (HPSD) ablation protocol using a conventional force-sensing equipped ablation catheter with surround-flow.

Methods

A total number of 101 patients undergoing RFA for AF were included. 33 patients treated with the DT catheter (50 W, 9 sec), were compared to 69 consecutive patients undergoing AI-guided AF ablation (AI anterior 550; AI posterior 400) with an open-irrigated catheter adherent to a 50 W HPSD protocol. Procedural data and recurrence rates were documented. Follow-up examinations were scheduled after 3, 6 and 12 months.

Results

Acute procedural success was achieved in all patients (n=101, 100%). DT-guided AF ablation was associated with a significantly longer mean procedure duration (98.8±30.1min vs. 78.2±25.6, p=0.002*). PVI using the DT ablation catheter required significantly more RF applications (75.4±30.8min vs. 61.3±14.1, p=0.019*). Total RF duration was significantly lower in the DT group (792.1±311.2sec vs. 1035.5±287.2sec, p<0.001*) as well as fluoroscopy time (4.6±2.1min vs.5.5±2.5min, p<0.006*) and dose (183.8±178.1yGym2 vs. 295.8±247.5yGym2, p<0.013*). Procedure related mayor complications occurred in 1 patient from the DT group (acute stroke; 3%) and in no patients from the HPSD cohort. Early recurrence was reported from 4 patients treated with the DT catheter (12%) compared to 8 patients undergoing HPSD RFA (12 %) (p=1.000).

Conclusion

Temperature- and power- controlled AF ablation using 50 W was safe and effective. AI-guided HPSD ablation resulted in significantly shorter procedure times with significantly fewer RF applications for PVI, whereas total RF duration and fluoroscopy times were significantly higher in this cohort. Further studies are needed to confirm this initial observation.

The novel POLARx ablation system improves cryothermal single-shot guided pulmonary vein isolation: impact of individual pulmonary vein anatomy

Funding Acknowledgements

Type of funding sources: None.

Background

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). Recently, a novel balloon-guided cryothermal single shot device (POLARx) was introduced.

Purpose

This observational study aimed to evaluate ablation efficacy and outcome using the novel POLARx CB system compared to the established one and to access the impact of individual PV characteristics on freedom from arrhythmia recurrence in paroxysmal (PAF) and persistent (PERS) AF.

Methods

666 patients undergoing CB-guided ablation for AF were included. 601 patients treated with the AFA ablation system (Arctic Front Advance Pro, AFA) were compared to 65 consecutive patients who underwent PVI using the POLARx. Individual anatomical characteristics of the left atrium and PVs were assessed using pre-procedural cardiac magnetic resonance imaging (MRI). For each PV, the cross-sectional orifice area (CSOA) was determined. Follow-up examinations were scheduled after 3 and 6 months.

Results

Acute PVI was achieved in all patients (100%). 6-months AF-free survival was significantly higher in the POLARx cohort (POLARx: n=45, 69%; AFA: n=359, 60%; Log-rank p=0.037*). This applies to PAF (n=42, 65%, p=0.033*), PERS (n=23, 35%, p<0.001*) and normal PV anatomy (2 left- and two right-sided PVs; n=57, 88%, p< 0.001*). MRI found a comparable percentage of patients with normal PV anatomy (POLARx: n=57, 88%; AFA: n=512, 85%, p=0.126). A higher amount of variant PV anatomy was revealed in patients with PERS AF (p=0.043*), but this factor was not predictive for AF-recurrence (PAF: p=0.610; PERS: p=0.096). PAF patients with AF-recurrence presented with significantly larger CSOA of the left sided PVs and the right superior PVs (LSPV: 224.8 ± 98.1 mm2 vs. 220.6 ± 64.8 mm2, p<0.001*; LIPV: 145.9 ± 63.2 mm2 vs. 140.4 ± 52.8 mm2, p<0.001*; RSPV 268.9 ± 79.3 mm2 vs. 262.3 ± 75.6 mm2, p<0.001*). In patients with PERS AF no association between CSOA and ablation outcome was observed. Multivariate Cox regression analyses identified the AFA ablation system (p=0.022*, hazard ratio (HR) 1.776, confidence interval (CI) 0.240-9.281) and PERS AF (p<0.001*, HR 6.608, CI 0.220-73.839) as independent predictors for AF-recurrence.

Conclusion

PVI using the POLARx system improves freedom from AF recurrence independent of individual anatomical considerations and PV occlusion rates. For PAF patients, a significant association between CSOA and the outcome after CB- guided PVI was demonstrated.

[MRI-based catheter ablation : Current status and outlook]

Fluoroscopy-based catheter ablation has established itself as a standard procedure for the treatment of patients with cardiac arrhythmias. However, it is subject to certain limitations with regard to the visualization of arrhythmogenic substrate and ablation lesions and is associated with radiation exposure. Within the framework of studies, initial experience with MRI-based, radiation-free electrophysiological examinations and ablations could be gained. The integration of MRI technology into electrophysiological procedures promises numerous advantages. The ability to operate in a radiation-free environment during MRI-based catheter ablation is significant and promising. Furthermore, MRI provides important procedure-relevant information in terms of visualization of individual arrhythmogenic substrate. In order to further improve immediate and long-term ablation success, especially in the context of complex arrhythmias and structural heart disease, the direct and successful integration of MRI-generated findings into the ablation process is of utmost importance. The future of MRI-based catheter ablation could thus lie in particular in the treatment of more complex cardiac arrhythmias, which require personalized therapy paths. In this respect, however, the data situation is still extremely limited. Further technical developments and larger studies are indispensable in order to gain further important insights into the feasibility, safety and success rate of MRI-based invasive electrophysiological diagnostics and therapy in comparison to conventional ablation methods.

Find me if you can: lessons learned using the novel cartofinder algorithm in a routine workflow for catheter ablation of atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

CARTOFINDER allows for a simultaneous and automated detection of repetitive focal and rotational activations during electroanatomical mapping using a multi-electrode catheter in patients with atrial fibrillation (AF).

Aim

This study aimed to validate the CARTOFINDER algorithm for the detection of potential drivers for AF under routine clinical conditions and to access the effects of PVI and additional substrate modification on regions of interests (ROI) from CARTOFINDER mapping.

Methods

Forty-four consecutive patients underwent AF ablation for persistent AF using a 3D-mapping system with the novel integrated CARTOFINDER module. All patients presented with persistent AF and mapping was performed using a multi-electrode catheter. The ablation workflow was divided into the following steps: 1. 3D reconstruction of the right (RA) and left atrium (LA). 2. Identification of the individual ROIs separated for focal and rotational activity in the RA and LA. 3. Ablation index guided pulmonary vein isolation (PVI). 4. Repeat mapping for ROIs in the RA and LA. 5. Direct current electrical cardioversion. 6. Confirmation of persistent PVI and bipolar ultra-high density mapping of the RA and LA followed by substrate modification if there was evidence for local bipolar low-voltage in the LA.

Results

Acute PVI was achieved in all patients (100%). In 28% of these patients additional LA substrate modification was performed. AF termination was observed in 4 patients. Mean procedure duration was 137 ± 30 min, mapping time for ROIs in the RA was 8 ± 5 min and 11 ± 5 for the LA, respectively. A mean number of 149 ± 82 ROIs were revealed from CARTOFINDER. In the LA, focal activity was predominantly observed inside the LA appendage (LAA) and in close relationship to the pulmonary vein ostia. The majority of rotational activities was found along the mitral valve annulus. In the RA, the majority of ROIs was found at the septum and in close relationship to the RA appendage. During re-mapping for ROIs after AF ablation we observed the elimination of ROIs close to the linear ablation set for PVI. In addition, rotational activity could not be re-identified at repeat mapping.

Conclusions

ROIs could be discriminated and visualized utilizing CARTOFINDER in all patients. These ROIs might potentially be an additional and individual ablation target beyond PVI in patients with persistent AF.

AV-node isolation in atrial fibrillation vs AV-node ablation by pace and ablate strategy

Funding Acknowledgements

Type of funding sources: None.

Introduction

AV-node ablation (AVNA) is a common therapy option for rate control strategy of permanent atrial fibrillation. However, this therapy has numerous side-effects as bundle branch blocks and absence of escape rhythm. We have invented a new technique that isolates the AV node instead of ablation.

Methods

Our study includes 60 patients with 40 being treated with AVNA and 20 being treated with AV-node isolation (AVNI). In AVNI patient´s AV-node region was mapped using 3D navigation system. Ablation was performed around the previously mapped HIS-cloud regions isolating the atrium from the AV-node. In all cases in AVNI group ablation was performed with irrigated tip ablation catheter.  Procedure time, ablation points, fluoroscopy time and total DAP, escape rhythm and delta QRS among other data were measured and compared in these two methods. Statistical analysis was performed by SPSS software 27.0.

Results

No complications appeared in this study. In the AVNI group more ablation points were used (p < 0.01) but there was no significant difference in total procedure time (p = 0.730). With AVNI highly significantly less fluoroscopy time (1.4 vs. 4.7 minutes) and total DAP (40.75 vs. 382.85 µGym²) was achieved (p < 0.01). Moreover, the median change in QRS width was 0 ms in the AVNI group vs. 26 ms in the AVNA group (p < 0.01). Immediately postoperative the escape rhythm of the AVNI group was significantly higher than in the AVNA group (MRang = 37.38 vs. MRang = 27.06, p = 0.023).

Conclusion

AV-node isolation using 3D navigation mapping system is a safe and effective alternative to classic AVNA procedure with less radiation exposure and potential preservation of escape rhythm, which is a major benefit in case of a pacemaker failure.

Figure 1. 3D Navigation pictures after successful AVNI with NavX-System (left panel) and CARTO 3-System (right panel). His cloud with yellow points. The Tricuspid annulus could be defined with different color (green on the left panel) or with the tag points (white points on the right panel). Modified left lateral to posterior view. Abstract Figure.

[Treatment of premature ventricular contractions in patients with structural heart disease : Insights from imaging]

The diagnosis of premature ventricular contractions (PVC) is presumptively based on the presence of frequent symptoms. Particularly in patients with a relatively low PVC burden, the relationship between the PVCs and an individual arrhythmia substrate can be challenging to ascertain. Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) has been found to be beneficial in identifying the presence of potential individual arrhythmia substrates even in patients with normal left ventricular function. Consequently, CMR has been useful in risk stratification of patients with PVCs. The authors aimed to demonstrate and discuss the current role and future use of CMR in the diagnostic algorithm to guide PVC ablation.

[Coherent mapping in adults with congenital heart disease : Role of the novel coherent mapping technique for treatment of atrial tachycardia in adults with congenital heart disease]

A 31-year-old woman with a surgically corrected double outlet right ventricle and recurrent narrow QRS complex tachycardia was admitted to our hospital. The patient was scheduled for electrophysiology study. Coherent mapping identified the critical isthmus as a slow conduction area within posterolateral intercaval scar tissue. A continuous line of ablation was applied resulting in termination of the atrial tachycardia at the site of the critical isthmus from coherent mapping. Thus, coherent mapping facilitates complex ablation procedures and improves efficacy and efficiency.

Hypercapnic ventilatory response in heart failure patients with central sleep-disordered breathing

Background

Sleep-disordered breathing (SDB) is a highly common comorbidity in heart failure (HF) patients and appears mainly as obstructive SDB, or central SDB. SDB has been shown to deteriorate quality of life in HF patients, but its presence is also associated with worse prognosis. SDB severity has been shown to mirror HF level and hereby hypercapnic ventilatory response (HCVR) depicts ventilation instability which furthermore expresses HF severity. But HCVR direct correlation with HF to predict HF severity has not been sufficiently studied yet.

Methods and results

We included 501 HF patients that received multichannel cardiorespiratory polygraphy, clinical workup for HF and HCVR in our center. The degree of SDB was graded with apnea-hypopnea-index (AHI) with guideline recommendation for treatment at an AHI >15/h. NT-Pro-BNP was obtained for HF quantification.

Mean age was 66.4±11 years, body mass index (BMI) 30.7±5 kg/m2 and mean HCVR was 2.56±1.18. 136 (27.2%) patients had central SDB with a proportion of 124 (24.8%) having moderate to severe SDB (AHI >15/h). 345 (68.9%) had obstructive SDB with moderate to severe SDB in 296 (59.1%) patients. Differences were detected for HCVR and HF in the central SDB group with a HCVR of 2.78±1.4 and NT-Pro-BNP of 2835.88±10536.4 pg/ml, while the OSA group shows a HCVR of 2.5±1 and NT-Pro-BNP of 929.9±1781.

Linear regression identified HCVR (p=0.045) and NT-Pro-BNP (p=0.034) to independently correlate with central SDB and in addition HCVR was also significantly associated with NT-Pro-BNP (p=0.007).

Conclusion

HF severity is closely linked to both NT-Pro-BNP and central SDB. HCVR seems to have the potential to predict manifestation of central SDB and increased NT-Pro-BNP values in HF. HCVR may be an easily obtainable parameter to identify both HF severity and presence of central SDB in HF patients.

Funding Acknowledgement

Type of funding source: None

6121Phrenic nerve injury during pulmonary vein isolation using the second-generation cryoballoon: characteristics and follow-up - The YETI registry

Background

Second-generation cryoballoon (CB2) based pulmonary vein isolation (PVI) has emerged as a safe and effective treatment option for symptomatic atrial fibrillation (AF). Although published complication rates of CB2 based-PVI are relatively low and several safety algorithms have been implemented in the protocols the most frequent complication is right-sided phrenic nerve injury (PNI). The reported incidence of PNI varies from 2–5% of patients. However data on PNI characteristics as well as follow-up is sparse.

Purpose

We aimed to evaluate the incidence, characteristics and outcome of PNI during after CB2 based-PVI in a large patients population.

Methods and results

From July 2012 to November 2018 a total of 13693 patients received CB2 or CB3 (third-generation) based-PVI in 23 EP centers (Germany: 12, China: 1, Turkey: 3, Japan: 3, USA: 1, Austria: 1, Poland: 1, Swizerland: 1). A total of 596 (4.4%) of patients experienced PNI during treatment of the right superior (84%) right inferior (15%) right middle (0.3%) (and left superior (0.3%) pulmonary veins. The mean time to PNI was 127±51 seconds and the mean temperature at the time of PNI was −49±7 °C. The target PV was isolated at time of PNI in 84% of cases. The applications were interrupted using double-stop technique in (71%). In 212/306 (52%) a CMAP was utilized.

At the end of the procedure PNI persistent in 45% of patients. Fluoroscopic or sonographic evaluation of PNI was performed 1–3 days after the procedure and revealed persistent PNI in 35% of patients. Dyspnea before discharge was reported in 18% of patients with persistent PNI. Patients follow up at 1–3, and 6–12 months included fluoroscopy and a visit in an outpatient clinic. After 1–3 months 18% of patients showed persistent PNI including 13% of patients complaining of dyspnea. After 6–12 months of follow-up including fluoroscopic evaluation PNI was persistent in 1.8% of patients while dyspnea was reported by 1.7% patients. Only 0.08% of the overall population of 13693 patients showed permanent and symptomatic PNI.

Conclusion

The incidence of PNI during CB2-based PVI is low. About 55% of PNI recovered until the end of the procedure. Most of PNI recovered within 12 months. Symptomatic permanent PNI is very rare in patients after CB2/CB3-based PVI.

P1883Arrhythmias in transplanted hearts: Lessons from Europes largest cohort of patients who underwent orthotopic heart transplantation

Introduction

Cardiac arrhythmias are regulary seen in patients following orthotopic heart transplantation (OHT). So far, there is no data available about the prevalence in a large cohort.

Methods

We retrospectively screened our database for subjects with OHT who received inpatient or outpatient treatment in our center between January 2000 and December 2018. All these patients were carefully reviewed with special attention to rhythm disturbances after successful transplantation.

Results

We identified a total number of 1890 subjects with history of OHT being treated in our center during the pre-defined time-period. The prevalence of supraventricular tachycardias was as follows: atrial fibrillation/atypical flutter and atrial ectopy 10%, AV-node-re-entry tachycardia 3%, typical atrial flutter 2% and higher degree AV-Block or Sick-Sinus-Syndrom (SSS) was 6%. Sustained ventricular tachycardia or ventricular premature contractions were present in 2%. Regarding the patients with arrhythmias, 13% received catheter ablation for arrhythmias, thereof 53% an atrial ablation (24% left atrial ablation), the remainder received a ventricular ablation.

Conclusion

In this very large cohort and following a long observational time, there was a higher incidence of atrial arrhythmias in patients following OHT as reported in healthy subjects with an emphasis on atrial fibrillation and flutter. This data gives a valuable background information on morbidity following OHT.

P6566Noninvasive Panoramic Mapping of Phase Singularities with Signal Complexity Analysis in Patients with Persistent Atrial Fibrillation

Background

An assessment of positive outcome probability of ablation therapy based on the comprehensive signal complexity analysis is a promising working hypothesis while electrocardiographic imaging (ECGI) can detect and visualize zones of phase singularities (PS) associated with stable sources of atrial fibrillation (AF).

Methods

Ten consecutive patients with persistent AF (three female, median (min–max) – 63.5 (45–75) years) underwent ECGI using “Amycard 01C EP lab” system with cardiac MRI (1.5-T Magnetom Avanto) followed by pulmonary vein isolation. Each T-Q segment with a length >800 ms during AF was processed to find PS. Sites with rotations around stable pivot points were considered as PS and then marked and visualized on the reconstructed anatomical 3D atrial model. Finally, a signal complexity cluster analysis was performed to define and depict phase-aggregation zones.

Results

ECGI analysis identified a total number of 410 PS, with 196 (47.8%) occurring in the LA and 214 (52.2%) in the RA. The median (25–75% IQR) number of revealed PS per patient was n=20 (14–30) for RA and n=20 (11–22) for the LA. The majority of the PS in the LA was located on the inferior wall n=66 (min-max 1–17). In eight patients, comprehensive signal complexity analysis revealed stability of phase-clustered zones over time. The mean number (min-max) of PS in a clustered area was 10 (6–15). In two patients, PS were distributed disordered on the entire LA and RA surface.

Distribution of phase singularities

Conclusions

This is the first clinical study demonstrating signal complexity analysis capability of clustering noninvasively mapped PS and relating them to specific atrial anatomical regions. Thereby obtained clusters may be a potential zones of conduction block, and could contribute to a better understanding of the temporal AF complexity.

Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus: comparison to transesophageal echocardiography

PURPOSE

Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent.

MATERIALS AND METHODS

A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6 % male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay.

RESULTS

In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE.

CONCLUSION

MDCT was 100 % accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

KEY POINTS

• Patients with no filling defect or thrombus in MDCT in the LA/LAA region are unlikely to have thrombus and may undergo PVI without TEE.• Here, the role of an additional TEE in pre-procedural management prior to PVI in patients with AF has to be redefined.• Using a split-bolus injection protocol increases the diagnostic accuracy of thrombus in the LA/LAA region.

Effects of different proton pump inhibitors on cardiac contractility in isolated human failing myocardium

AIM

Proton pump inhibitors (PPI), e.g. pantoprazole (PP), esomeprazole (EP) and omeprazole (OP), work as anti-ulcer/gastrointestinal reflux drugs. Also, they are widely used in postoperative care of patients in cardiac surgery to prevent upper gastrointestinal bleeding. Therefore, in western industrial countries they play a major economic role, representing one of the most important drugs in open heart cardiac surgery.

METHODS

Intact muscle strips (n=32) were isolated from the right ventricle wall of failing human hearts. In four different groups (PP, EP, OP, control group, each n=8), force amplitudes were recorded at a frequency of 60 beats per minute (bpm) with increasing PPI concentrations (0 to 320 µm/mL).

RESULTS

In isometrically contracting muscle strips, significant negative inotropic effects were observed in the presence of all three PPI-groups (PP, EP and OP) with doses of 2.5 µg/mL and higher compared to the control group (p < 0.05 each). With high doses (320 µm/mL), force amplitudes could be almost completely depressed. The half maximal inhibitory concentration (IC50) for EP was 35.7 (confidence interval: 17.3-73.6) vs. OP 29.3 (6.8-126.6) vs. PP 25.1 (14.6-43.1) µg/mL (n.s.). No significant differences were found between the different proton pump inhibitors (PP, EP, OP) throughout the range of all concentrations. Relaxation was impaired in all PPI subgroups with prolonged time to 90% relaxation (RT90%) and maximum relaxation velocity (‑df/dt) was reduced, too. These effects were partially reversible after wash-out of the drugs.

CONCLUSION

We conclude that proton pump inhibitors show significant negative inotropic effects on isolated human failing myocardium. There is no apparent difference seen in the magnitude of the effects of each PPI-group. Further, in-vivo investigations are necessary to reveal the clinical evidence of PPI's negative inotropic effects, e.g. in cardio-surgical patients with heart failure.

[Current role of amiodarone in antiarrhythmic therapy]

Decades after its registration, amiodarone is still regarded as the most effective antiarrhythmic drug available for the treatment of tachyarrhythmias. Amiodarone is classified as a class III antiarrhythmic drug. In addition to the prolongation of cardiac repolarization, its leading pharmacologic features are sodium and calcium channel block, nonselective β-adrenergic inhibition as well as high lipophilicity and a very long plasma half-life. In patients with paroxysmal atrial fibrillation, amiodarone is the most effective antiarrhythmic drug in maintaining sinus rhythm. Furthermore, it prevents ventricular arrhythmias, such as frequent ventricular extrasystoles or nonsustained runs of ventricular tachycardia, as well as sustained ventricular tachycardia and ventricular fibrillation. In patients with increased risk for sudden cardiac death, e.g., with severely depressed left ventricular function, amiodarone is a highly effective and safe antiarrhythmic drug. In addition, amiodarone has been shown to reduce the number of appropriate and inappropriate shocks in patients with an implantable cardioverter-defibrillator. During long-term amiodarone treatment, typical side effects including corneal microdeposits, blue-gray skin discoloration, photosensitivity, hypothyroidism, hyperthyroidism, peripheral neuropathy, optical neuritis and hepatotoxicity accrue. Upon cessation of medication, these are almost always reversible. Irreversible, severe adverse effects, such as pulmonary toxicity, are very rare under the currently used maintenance dose of 200 mg/day. With regard to its side effect profile, an adequate follow-up of patients including laboratory values, lung function tests, and visual acuity is necessary.

Retrospektive Analyse eines computerassistierten Detektions-Systems (CAD) in der digitalen Vollfeldmammographie in Abhängigkeit von der Histologie

PURPOSE

To evaluate the usefulness of a computer-aided detection (CAD) system in full-field digital mammography in correlation to tumor histology.

MATERIAL AND METHODS

A total of 476 patients (226 patients with histologically proven malignant tumors, 250 healthy women) took part in this study. The mammograms were studied retrospectively, using the CAD system Image Checker. For 226 patients digital mammograms in MLO-projection were available. For 186 of these patients the CC-projection was also available. CAD markers that correlated with histologically proven carcinomas were considered to be true-positive markers. All other CAD markers were considered to be false-positive. Histologically proven carcinomas without markers were false-negative results. The dependence of the CAD markers placement upon the different carcinoma histologies was studied using the Chi-square test.

RESULTS

No significant difference could be proven for the detectability of malignant breast lesions of different histologic types. For the detectability of ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC), invasive lobular carcinoma (ILC), lobular carcinoma in situ (LCIS), tubular carcinoma and ductulo-lobular carcinoma, the true positives were 71.1 %, 75 %, 70.7 %, 70 %, 60 % and 80 %, respectively, in the MLO projection and 83.9 %, 75.9 %, 81.8 %, 77.8 %, 87.5 % and 33.3 %, respectively, in the CC projection. There was an average of 0.5 false-positive markers per mammographic image.

CONCLUSION

The histologic type of carcinoma seems to have no influence on detectability when using the CAD system. The high rate of false-positive markers shows, however, the limited specificity of the CAD system and that improvements are necessary.