Patient-specific quantification of cardiorespiratory motion for cardiac stereotactic radioablation treatment planning.

Background: Cardiac radioablation is a new treatment for patients with refractory ventricular tachycardia (VT). The target for cardiac radioablation is subject to cardiorespiratory motion (CRM), the heart's movement with breathing and cardiac contraction. Data regarding the magnitude of target CRM are limited but are highly important for treatment planning. Objectives: The study sought to assess CRM amplitude by using ablation catheter geometrical data. Methods: Electroanatomic mapping data of patients undergoing catheter ablation for VT at 3 academic centers were exported. The spatial position of the ablation catheter as a function of time while in contact with endocardium was analyzed and used to quantify CRM. Results: Forty-four patients with ischemic and nonischemic cardiomyopathy and VT contributed 1364 ablation lesions to the analysis. Average cardiac and respiratory excursion were 1.62 ± 1.21 mm and 12.12 ± 4.10 mm, respectively. The average ratio of respiratory to cardiac motion was approximately 11:1. CRM was greatest along the craniocaudal axis (9.66 ± 4.00 mm). Regional variations with respect to respiratory and cardiac motion were observed: basal segments had smaller displacements vs midventricular and apical segments. Patient characteristics (previous cardiac surgery, height, weight, body mass index, and left ventricular ejection fraction) had a statistically significant, albeit clinically moderate, impact on CRM. Conclusion: CRM is primarily determined by respiratory displacement and is modulated by the location of the target and the patient's biometric characteristics. The patient-specific quantification of CRM may allow to decrease treatment volume and reduce radiation exposure of surrounding organs at risk while delivering the therapeutic dose to the target.

Differences in underlying cardiac substrate among S-ICD recipients and its impact on long-term device-related outcomes: Real-world insights from the iSUSI registry.

BACKGROUND: Outcome comparisons among subcutaneous implantable cardioverter-defibrillator (S-ICD) recipients with nonischemic cardiomyopathies are scarce. OBJECTIVE: The aim of this study was to evaluate differences in device-related outcomes among S-ICD recipients with different structural substrates. METHODS: Patients enrolled in the i-SUSI (International SUbcutaneouS Implantable cardioverter defibrillator registry) project were grouped according to the underlying substrate (ischemic vs nonischemic) and subgrouped into dilated cardiomyopathy, hypertrophic cardiomyopathy, Brugada syndrome (BrS), arrhythmogenic right ventricular cardiomyopathy (ARVC). The main outcome of our study was to compare the rates of appropriate and inappropriate shocks and device-related complications. RESULTS: Among 1698 patients, the most common underlying substrate was ischemic (31.7%), followed by dilated cardiomyopathy (20.5%), BrS (10.8%), hypertrophic cardiomyopathy (8.5%), and ARVC (4.4%). S-ICD for primary prevention was more common in the nonischemic cohort (70.9% vs 65.4%; P = .037). Over a median (interquartile range) follow-up of 26.5 (12.6-42.8) months, no differences were observed in appropriate shocks between ischemic and nonischemic patients (4.8%/y vs 3.9%/y; log-rank, P = .282). ARVC (9.0%/y; hazard ratio [HR] 2.492; P = .001) and BrS (1.8%/y; HR 0.396; P = .008) constituted the groups with the highest and lowest rates of appropriate shocks, respectively. Device-related complications did not differ between groups (ischemic: 6.4%/y vs nonischemic: 6.1%/y; log-rank, P = .666), nor among underlying substrates (log-rank, P = .089). Nonischemic patients experienced higher rates of inappropriate shocks than did ischemic S-ICD recipients (4.4%/y vs 3.0%/y; log-rank, P = .043), with patients with ARVC (9.9%/y; P = .001) having the highest risk, even after controlling for confounders (adjusted HR 2.243; confidence interval 1.338-4.267; P = .002). CONCLUSION: Most S-ICD recipients were primary prevention nonischemic cardiomyopathy patients. Among those, patients with ARVC tend to receive the most frequent appropriate and inappropriate shocks and patients with BrS the least frequent appropriate shocks.

A worldwide survey on incidence, management, and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: the POTTER-AF study.

AIMS: Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management, and outcome are sparse. METHODS AND RESULTS: This international multicentre registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553 729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed, at 214 centres in 35 countries. In 78 centres 138 patients [0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (P < 0.0001)] were diagnosed with an oesophageal fistula. Peri-procedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8% and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) [odds ratio 7.463 (2.414, 23.072) P < 0.001]. CONCLUSION: Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high.

Impact of cryoballoon application abortion due to phrenic nerve injury on reconnection rates: a YETI subgroup analysis.

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 (PNI) which is leading to premature abortion of the freeze cycle. Here, we analysed reconnection rates after CB-based PVI and PNI in a large-scale population during repeat procedures. METHODS AND RESULTS: In the YETI registry, a total of 17 356 patients underwent CB-based PVI in 33 centres, and 731 (4.2%) patients experienced PNI. A total of 111/731 (15.2%) patients received a repeat procedure for treatment of recurrent AF. In 94/111 (84.7%) patients data on repeat procedures were available. A total of 89/94 (94.7%) index pulmonary veins (PVs) have been isolated during the initial PVI. During repeat procedures, 22 (24.7%) of initially isolated index PVs showed reconnection. The use of a double stop technique did non influence the PV reconnection rate (P = 0.464). The time to PNI was 140.5 ± 45.1 s in patients with persistent PVI and 133.5 ± 53.8 s in patients with reconnection (P = 0.559). No differences were noted between the two populations in terms of CB temperature at the time of PNI (P = 0.362). The only parameter associated with isolation durability was CB temperature after 30 s of freezing. The PV reconnection did not influence the time to AF recurrence. CONCLUSION: In patients with cryoballon application abortion due to PNI, a high rate of persistent PVI rate was found at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03645577?term=YETI&cntry=DE&draw=2&rank=1 ClinicalTrials.gov Identifier: NCT03645577.

Adjunctive Left Atrial Posterior Wall Isolation in Treating Atrial Fibrillation: Insight From a Large Secondary Analysis.

OBJECTIVES: This study evaluated the role of adjunctive left atrium posterior wall isolation (PWI) in preventing atrial fibrillation (AF) recurrence. BACKGROUND: The left atrium posterior wall is an arrhythmogenic substrate that contributes to the development of AF. METHODS: This was an updated pooled analysis that included clinical data regarding PWI plus pulmonary vein isolation (PVI) in treating AF. The primary outcome was recurrence of atrial tachyarrhythmias. RESULTS: A total of 26 studies with 3,287 patients with AF (age 61.7 ± 10.8 years) were included. Mean follow-up was 15.2 ± 8.4 months. Procedural success to achieve PWI was 92.8%. In paroxysmal AF, adjunctive PWI did not reduce the recurrence of all atrial arrhythmias (P = 0.21) or AF (P = 0.37); however, in persistent AF, adjunctive PWI was associated with substantially lower recurrence of all atrial arrhythmias (risk ratio: 0.74; P < 0.001) and AF (risk ratio: 0.67; P = 0.01), particularly when randomized data were included. Subgroup analyses based on meta-regression demonstrated that patients with older age, a larger left atrial diameter, and persistent AF benefited more significantly from the adjunctive PWI. Adjunctive PWI using either radiofrequency or a cryoballoon reduced AF recurrence, whereas using radiofrequency seemed to be associated with higher recurrence rate of atrial tachycardias and/or atrial flutter. Non-BOX adjunctive PWI rather than BOX PWI was associated with significantly lower recurrence of AF. The incidence of procedural adverse events between the PVI+PWI (3.2%) and PVI (2.8%) groups was low and similar. PVI+PWI needed longer ablation and/or procedural time but had similar fluoroscopy time. CONCLUSIONS: Adjunctive PWI can be achieved in most patients without compromising safety. Patients with persistent AF appear to benefit from this approach. The ablation technology and/or approach may affect the clinical outcome of PWI.

Phrenic Nerve Injury During Cryoballoon-Based Pulmonary Vein Isolation: Results of the Worldwide YETI Registry.

BACKGROUND: Cryoballoon-based pulmonary vein isolation (PVI) has emerged as an effective treatment for atrial fibrillation. The most frequent complication during cryoballoon-based PVI is phrenic nerve injury (PNI). However, data on PNI are scarce. METHODS: The YETI registry is a retrospective, multicenter, and multinational registry evaluating the incidence, characteristics, prognostic factors for PNI recovery and follow-up data of patients with PNI during cryoballoon-based PVI. Experienced electrophysiological centers were invited to participate. All patients with PNI during CB2 or third (CB3) and fourth-generation cryoballoon (CB4)-based PVI were eligible. RESULTS: A total of 17 356 patients underwent cryoballoon-based PVI in 33 centers from 10 countries. A total of 731 (4.2%) patients experienced PNI. The mean time to PNI was 127.7±50.4 seconds, and the mean temperature at the time of PNI was -49±8°C. At the end of the procedure, PNI recovered in 394/731 patients (53.9%). Recovery of PNI at 12 months of follow-up was found in 97.0% of patients (682/703, with 28 patients lost to follow-up). A total of 16/703 (2.3%) reported symptomatic PNI. Only 0.06% of the overall population showed symptomatic and permanent PNI. Prognostic factors improving PNI recovery are immediate stop at PNI by double-stop technique and utilization of a bonus-freeze protocol. Age, cryoballoon temperature at PNI, and compound motor action potential amplitude loss >30% were identified as factors decreasing PNI recovery. Based on these parameters, a score was calculated. The YETI score has a numerical value that will directly represent the probability of a specific patient of recovering from PNI within 12 months. CONCLUSIONS: The incidence of PNI during cryoballoon-based PVI was 4.2%. Overall 97% of PNI recovered within 12 months. Symptomatic and permanent PNI is exceedingly rare in patients after cryoballoon-based PVI. The YETI score estimates the prognosis after iatrogenic cryoballoon-derived PNI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03645577. Graphic Abstract: A graphic abstract is available for this article.

Pulmonary Vein Isolation With Very High Power, Short Duration, Temperature-Controlled Lesions: The QDOT-FAST Trial.

OBJECTIVES: This study sought to evaluate the safety and short-term performance of a novel catheter for very high power-short duration (vHPSD) ablation in the treatment of paroxysmal atrial fibrillation. BACKGROUND: The vHPSD catheter is a novel contact force-sensing catheter optimized for temperature-controlled radiofrequency ablation with microelectrodes and 6 thermocouples for real-time temperature monitoring; the associated vHPSD algorithm modulates power to maintain target temperature during 90 W, 4 s lesions. METHODS: QDOT-FAST (Clinical Study for Safety and Acute Performance Evaluation of the THERMOCOOL SMARTTOUCH SF-5D System Used With Fast Ablation Mode in Treatment of Patients With Paroxysmal Atrial Fibrillation) is a prospective, multicenter, single-arm study enrolling patients with symptomatic paroxysmal atrial fibrillation indicated for catheter-based pulmonary vein isolation. Primary endpoints were short-term effectiveness (confirmation of entrance block in all targeted pulmonary veins after adenosine/isoproterenol challenge) and short-term safety (primary adverse events). Participants were screened for silent cerebral lesions by magnetic resonance imaging. Patients were followed for 3 months post-ablation. RESULTS: A total of 52 patients underwent ablation and completed follow-up. Pulmonary vein isolation was achieved in all patients using the study catheter alone, with total procedure and fluoroscopy times of 105.2 ± 24.7 min and 6.6 ± 8.2 min, respectively. Most patients (n = 49; 94.2%) were in sinus rhythm at 3 months. Two primary adverse events were reported: 1 pseudoaneurysm; and 1 asymptomatic thromboembolism. There were no deaths, stroke, atrioesophageal fistula, pulmonary vein stenosis, or unanticipated adverse device effects. Six patients had identified silent cerebral lesions-all classified as asymptomatic without clinical or neurologic deficits. CONCLUSIONS: This first-in-human study of a novel catheter with optimized temperature control demonstrated the clinical feasibility and safety of vHPSD ablation. Procedure and fluoroscopy times were substantially lower than historical standard ablation with point-by-point catheters. (Clinical Study for Safety and Acute Performance Evaluation of the THERMOCOOL SMARTTOUCH SF-5D System Used With Fast Ablation Mode in Treatment of Patients With Paroxysmal Atrial Fibrillation [QDOT-FAST]; NCT03459196).

Association of Preoperative Renin-Angiotensin System Inhibitors With Prevention of Postoperative Atrial Fibrillation and Adverse Events: A Systematic Review and Meta-analysis.

Importance: Postoperative atrial fibrillation (POAF) is a well-known complication after cardiac surgery. Renin-angiotensin system inhibitors (RASIs) have been suggested as an upstream therapy for selected patients with AF; however, evidence in the surgical setting is limited. Objective: To evaluate the role of preoperative RASIs in prevention of POAF and adverse events for patients undergoing cardiac surgery. Data Sources: The PubMed database and the Cochrane Library from inception until December 31, 2018, were searched by using the keywords renin-angiotensin system inhibitors OR angiotensin-converting enzyme inhibitors OR angiotensin receptor blocker OR aldosterone antagonist AND cardiac surgery. ClinicalTrials.gov was searched from inception until December 31, 2018, by using the keywords postoperative atrial fibrillation. Study Selection: Randomized clinical trials (RCTs) and observational studies comparing the association between preoperative RASI treatment vs no preoperative RASI treatment (control group) and the incidence of POAF were identified. Eleven unique studies met the selection criteria. Data Extraction and Synthesis: Pooled analysis was performed using a random-effects model. Sensitivity and subgroup analyses of RCTs were performed to test the stability of the overall effect. Metaregression was conducted to explore potential risk of bias. Main Outcomes and Measures: The primary outcome was POAF, and the secondary outcomes included rates of stroke and mortality and duration of hospitalization. Results: Eleven unique studies involving 27 885 unique patients (74.4% male; median age, 65 years [range, 58.5-74.5 years]) were included. Compared with the control group, the RASI group did not have a significantly reduced risk of POAF (odds ratio [OR], 1.04; 95% CI, 0.91-1.19; P = .55; z = 0.60), stroke (OR, 0.86; 95% CI, 0.62-1.19; P = .37; z = 0.90; without significant heterogeneity, P = .11), death (OR, 1.07; 95% CI, 0.85-1.35; P = .56; z = 0.59; without significant heterogeneity, P = .12), composite adverse cardiac events (OR, 1.04; 95% CI, 0.91-1.18; P = .58; z = 0.56), or a reduced hospital stay (weighted mean difference, -0.04; 95% CI, -1.05 to 0.98; P = .94; z = 0.07) using a random-effects model. Pooled analysis focusing on RCTs showed consistent results. The primary overall effect was maintained in sensitivity and subgroup analyses. Metaregression showed that male sex was significantly associated with POAF (τ2 = 0.0065; z = 3.47; Q = 12.047; P < .001) and that use of ß-blockers was associated with a significantly reduced risk in developing POAF (τ2 = 0.018; z = -2.24; Q = 5.0091; P = .03). Conclusions and Relevance: The findings from this study suggest that preoperative RASI treatment does not offer additional benefit in reducing the risk of POAF, stroke, death, and hospitalization in the setting of cardiac surgery. The results provide no support for conventional use of RASIs for the possible prevention of POAF and adverse events in patients undergoing cardiac surgery; further randomized data, particularly among those patients with heart failure, are needed.

Optimizing radiofrequency ablation of paroxysmal and persistent atrial fibrillation by direct catheter force measurement-a case-matched comparison in 198 patients.

BACKGROUND: Sufficient electrode-tissue contact is crucial for adequate lesion formation in radiofrequency catheter ablation (RFCA). OBJECTIVE: We assessed the impact of direct catheter force measurement on acute procedural parameters and outcome of RFCA for paroxysmal and persistent atrial fibrillation (AF). METHODS: Ninety-nine consecutive patients (70% men) with paroxysmal (63.6%) or persistent AF underwent left atrial RFCA using a 3.5-mm open-irrigated-tip (OIT) catheter with contact force measurement capabilities (group 1). For comparison a case-matched cohort with standard OIT catheters was used (99 patients; group 2). Case matching included gender, type of AF, number or RFCA procedures, and type of procedure. RESULTS: Procedural data showed a significant decline in radiofrequency ablation time from 52 ± 20 to 44 ± 16 minutes (P = 0.003) with a remarkable mean reduction in overall procedure time of 34 minutes (P = 0.0001; 225.8 ± 53.1 vs 191.9 ± 53.3 minutes). In parallel, the total fluoroscopy time could be significantly reduced from 28.5 ± 11.0 to 19.9 ± 9.3 minutes (P = 0.0001) as well as fluoroscopy dose from 74.1 ± 58.0 to 56.7 ± 38.9 Gy/cm(2) (P = 0.016). Periprocedural complications were similar in both groups. CONCLUSIONS: The use of contact force sensing technology is able to significantly reduce ablation, procedure, and fluoroscopy times as well as dose in RFCA of AF in a mixed case-matched group of paroxysmal and persistent AF. Energy delivery is substantially reduced by avoiding radiofrequency ablation in positions with insufficient surface contact. Additionally 12-month outcome data showed increased efficacy. Such time saving and equally safe technology may have a relevant impact on laboratory management and increased cost effectiveness.

MediGuide in supraventricular tachycardia: initial experience from a multicentre registry.

AIMS: Currently, fluoroscopy-based catheter visualization is the standard modality in invasive electrophysiological procedures. Recently a new technology for non-fluoroscopic visualization of diagnostic (since 2010) and ablation catheters (since May 2012) has been introduced. The MediGuide™-Technology (MediGuide) projects catheter tips on prerecorded cine loops in a high time resolution. METHODS AND RESULTS: We report on MediGuide-based supraventricular tachycardia (SVT) cases [atrioventricular nodal reentry tachycardia (AVNRT), atrioventricular reentry tachycardia (AVRT), Wolff-Parkinson-White syndrome (WPW), ectopic atrial tachycardia (EAT) and typical atrial flutter) from two European centres. In all patients, diagnostic and/or ablation catheters with a special sensor were used to perform the ablation procedures. All procedural data such as acute success, duration of the procedure, fluoroscopy time, and dose and patients' characteristics were analyzed and compared with conventionally ablated patients (n = 1865). Procedure-related complications during the hospital stay were recorded. A total of 24 consecutive patients were analyzed: no significant difference to the control group was seen in the baseline characteristics. The MediGuide patients were predominantly male (66%), aged 58 ± 14 years and were ablated for 6 AVNRT (25%), 4 AVRT/WPW (17%), 1 EAT (4%), and 13 typical atrial flutter (54%). The acute success rate was 100% (98% in the control group, n.s.). The median fluoroscopy time was 0.5 ± 1.4 min (10.2 ± 9.6 in the control group, P < 0.001), the median fluoroscopy dose was 187 ± 554 cGy cm(2) (996 ± 2593 cGy cm(2), P < 0.05). Mean procedure time was 70 ± 25 min (60 ± 36 min, n.s.). No complications during the hospital stay were recorded. CONCLUSION: In several different forms of supraventricular tachycardias the MediGuide-Technology contributed to a dramatic reduction in irradiation exposure. With a median fluoroscopy time of 30 s all SVT cases were effectively performed with no complications; the fluoroscopy burden can be significantly reduced not only for the patient but also for the nurses and the physicians performing the case. The overall procedure times are not prolonged due to the use of MediGuide Technology compared with a control group of >1800 patients undergoing conventional ablation procedures.

Identification of a high-risk population for esophageal injury during radiofrequency catheter ablation of atrial fibrillation: procedural and anatomical considerations.

BACKGROUND: Atrioesophageal fistula is an uncommon but life-threatening complication of atrial fibrillation (AF) ablation. Esophageal ulcerations (ESUL) have been proposed to be potential precursor lesions. OBJECTIVE: The purpose of our study was to prospectively investigate the incidence of ESUL in a large patient population undergoing radiofrequency catheter ablation (RFA). Additionally, we aimed to link demographic data and lesion sets with anatomical information given by multislice computed tomography imaging and to correlate these data with the development of ESUL. METHODS: This study included 267 patients and consecutively screened all individuals for evidence of ESUL 24 h after RFA of AF by endoscopy of the esophagus. A standardized ablation approach using a 25-W energy maximum at the posterior left atrial (LA) wall without esophagus visualization, temperature monitoring, or intracardiac ultrasound was performed. RESULTS: In total, we found 2.2% of patients (6 of 267) presenting with ESUL. Parameters exposing a specific patient to risk of developing ESUL in univariate analysis were persistent AF (5 of 95, P = .023), additional lines performed (roofline: 6 of 114, P = .006; LA isthmus: 4 of 49, P = .011; coronary sinus: 5 of 66, P = .004), and LA enlargement (P = .001) leading to sandwiching of the esophagus between the LA and thoracic spine. Multivariate analysis revealed LA-to-esophagus distance as the only significant risk factor. CONCLUSION: This study is the first to link anatomical information and procedural considerations to the development of ESUL in radiofrequency ablation for AF. Furthermore, it reveals the correlation and individual impact of these factors. Not a single patient with pulmonary vein isolation alone developed ESUL.

Acute development of gastroesophageal reflux after radiofrequency catheter ablation of atrial fibrillation.

BACKGROUND: Induction of gastroesophageal reflux after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) may have an impact on the progression of esophageal injury. OBJECTIVE: The purpose of this study was to assess the acute effect of RFCA on distal esophageal acidity using leadless pH-metry capsules. METHODS: A total of 31 patients (27 male and 4 female; 25 with paroxysmal AF) who underwent RFCA and esophagoscopy 24 hours before and after ablation were assessed for reflux and esophageal lesions. A leadless pH-metry capsule was inserted into the lower esophagus to screen for pH changes, number and duration of refluxes, and the DeMeester score (a standardized measure of acidity and reflux). No patient had a history of reflux or was taking proton pump inhibitors within 4 weeks before and 24 hours after ablation. RESULTS: Five patients (16.1%) who presented with asymptomatic reflux prior to ablation were excluded from further examination. Of the remaining 26 patients, 5 (19.2%) demonstrated a significant pathologic increase in DeMeester score after ablation. No statistical differences in baseline parameters, method of sedation, ablation approach, and total energy delivered on the posterior wall were observed between patients with and those without a pathologic DeMeester score. One patient with asymptomatic reflux prior to ablation developed esophageal ulceration. CONCLUSION: A significant number of patients undergoing RFCA of AF develop pathologic acid reflux after ablation. In addition, a subgroup of patients has a preexisting condition of asymptomatic reflux prior to ablation. This finding may explain a potential mechanism for progression of esophageal injury to atrio-esophageal fistulas in patients undergoing RFCA.

3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors improve myocardial high-energy phosphate metabolism in men.

PURPOSE: We intended to prove that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors or statins have a beneficial impact on the human myocardial, high-energy, phosphate metabolism. METHODS: The present study included 18 male patients (mean age 49.8 +/- 10.3) with statin-treated, familiar hypercholesterolemia (FH) and 13 male patients with untreated FH (mean age 44.6 +/- 9.5). Twenty-six healthy male volunteers served as controls (mean age 44.2 +/- 12.1). Phosphorus-31, two-dimensional chemical shift imaging (31P 2D CSI) of the heart was performed in all subjects using a 1.5 Tesla whole-body magnetic resonance (MR) scanner. The ratios between phosphocreatine (PCr) and beta-adenosine-triphosphate (beta-ATP) were calculated for the left ventricular myocardium. Furthermore, echocardiographic evaluation and stress tests were performed in all individuals. RESULTS: The untreated patients with FH exhibited a significant decrease in left ventricular PCr to beta-ATP ratios (1.78 +/- 0.34) compared with statin-treated FH patients (2.15 +/- 0.26, p < 0.001) and healthy controls (2.04 +/- 0.26, p = 0.009). The left ventricular PCr-to-beta-ATP ratios of the treated FH patients were in the range of the healthy controls. CONCLUSIONS: Our study shows for the first time an-improvement of the high-energy, phosphate metabolism in the left ventricular myocardium of patients with statin-treated FH compared with untreated FH patients.