The absence of real-time pulmonary vein isolation during cryoballoon ablation is associated with atrial fibrillation recurrence and pulmonary vein reconnection : Insights from the Middelheim-PVI Registry 2

BACKGROUND

Absence of real-time pulmonary vein (PV) isolation (PVI) occurring in 15-40% of PVs during cryoballoon ablation (CBA) of atrial fibrillation (AF) raises doubt about adequate PVI. Aim of the present study is to determine whether real-time PVI during CBA is predictive of long-term clinical outcome and durability of PVI.

METHODS

Eight hundred three AF patients (64 ± 10 years, 68% males) undergoing CBA were studied. The cohort was divided in 4 groups according to the number of PVs without real-time PVI: none (N = 252 [31.4%]), 1 (N = 255 [31.8%]), 2 (N = 159 [19.8%]), and 3-4 (N = 137 [17.1]).

RESULTS

At 3 years, 279 (34.7%) patients had recurrence of AF of which 188 underwent repeat ablation. A vein without real-time PVI was associated with AF recurrence (HR = 1.275; 95% CI 1.134-1.433; p < 0.01), independent of persistent AF type (HR = 2.075; 95% CI 1.584-2.738; p < 0.01), left atrial diameter (HR = 1.050; 95% CI 1.028-1.072; p < 0.01), and diagnosis-to-ablation time (HR = 1.002; 95% CI 1.000-1.005; p = 0.04). Highest success was achieved with present real-time PVI in all veins (77.4%), gradually decreasing per increasing number of absent real-time PVI: 66.3% for 1 vein, 58.5% for 2, and 48.9% for 3-4 veins (p < 0.001). At repeat ablation (N = 188), PV reconnection was seen in 99/430 (23.0%) versus 83/288 (28.8%) veins with and without real-time PVI, respectively (p = 0.08). Right inferior PVs (RIPVs) with real-time PVI were less reconnected than RIPVs without real-time PVI: 29.7% versus 43.7% (p = 0.047).

CONCLUSION

The absence of real-time PVI during CBA independently predicts AF recurrence with a 30% gradual decrease in outcome per increase in veins without real-time PVI. Real-time PVI is particularly important for the RIPV to achieve durable PVI.

Electroanatomical mapping improves procedural outcomes of cryoballoon pulmonary vein isolation (the Achieve Plus study)

BACKGROUND

Validation of pulmonary vein (PV) isolation (PVI) using only the Achieve catheter following cryoballoon ablation (CBA) is imperfect since pulmonary vein potentials (PVP) can be recorded in only 50-85% of the veins and residual PVP are found in up to 4.3-7.6% of the isolated veins in remapping studies.

OBJECTIVE

To study if addition of electroanatomical mapping to Achieve catheter-guided CBA is superior for PVI.

METHODS

One hundred patients were randomized between Achieve catheter-guided CBA (control group; N = 50) and Achieve catheter-guided CBA with additional EnSite voltage maps performed pre- and post-CBA (Achieve Plus group; N = 50). Confirmation of PVI was done by circular mapping catheter (CMC) and EnSite mapping by a second blinded operator.

RESULTS

Despite apparent PVI in all PVs after CBA, incomplete PVI was present in 0 out of 50 patients (0%) and 0 out of 204 PVs in the Achieve Plus group versus 6 patients out of 50 (12%; P = 0.012) and 6 out of 203 PVs (3%; P = 0.013) in the control group. All 6 non-isolated PVs could be successfully isolated by additional cryoapplications. Procedure time was longer in the Achieve Plus group (75.76 ± 21.65 vs 66.06 ± 16.83 min; P = 0.014) with equal fluoroscopy times (14.85 ± 6.41 vs 14.33 ± 8.55; P = 0.732).

CONCLUSION

The addition of electroanatomical EnSite mapping to the Achieve catheter improves the PVI rate of CBA and could be considered for future use. Design and Results of the Achieve Plus study. The Achieve Plus study shows that the addition of electro-anatomical EnSite mapping to the Achieve catheter improves PVI rate of CBA and could be considered for future use. See text for further explanation.

ABBREVIATIONS

CBA: cryoballoon ablation; PVI: pulmonary vein isolation.

Randomized, double blind, placebo-controlled, safety and efficacy study of dutogliptin in combination with filgrastim in early recovery post-MI: rationale, design and first interim analysis

Background

Regenerative therapies offer new approaches to improve cardiac function after acute ST-elevation myocardial infarction (STEMI). Mobilization of stem cells and homing within the infarcted area have been identified as the key mechanisms for successful treatment. Application of granulocyte-colony stimulating factor (G-CSF) is the least invasive way to mobilize stem cells while DDP4-inhibitor facilitates homing via stromal cell-derived factor 1 alpha (SDF-1α). Dutogliptin, a novel DPP4 inhibitor, combined with stem cell mobilization using G-CSF significantly improved survival and reduced infarct size in a murine model.

Purpose

We initiated a phase II, multicenter, randomized, placebo-controlled efficacy and safety study (N=140) analyzing the effect of combined application of G-CSF and dutogliptin, a small molecule DPP-IV-inhibitor for subcutaneous use after acute myocardial infarction.

Methods

The primary objective of the study is to evaluate the safety and tolerability of dutogliptin (14 days) in combination with filgrastim (5 days) in patients with STEMI (EF &lt;45%) following percutaneous coronary intervention (PCI). Preliminary efficacy will be analyzed using cardiac magnetic resonance imaging (cMRI) to detect &gt;3.8% improvement in left ventricular ejection fraction (LV-EF). 140 subjects will be randomized to filgrastim plus dutogliptin or matching placebos.

Results

Baseline characteristics of the first 26 patients randomized (24 treated) in this trial reveal a majority of male patients (70.8%) and a medium age of 58.4 years (37 to 84). During the 2-week active treatment period, 35 adverse events occurred in 13 patients, with 4 rated as serious (hospitalization due to pneumonia N=3, hospitalization due to acute myocardial infarction N=1), and 1 adverse event was rated as severe (fatal pneumonia), 9 moderate, and 25 as mild. 6 adverse events were considered possibly related to the study medication, including cases of increased hepatic enzymes (N=3), nausea (N=1), subcutaneous node/suffusion (N=1) and syncope (N=1).

Conclusions

Our data demonstrate that the combined application of dutogliptin and G-CSF appears to be safe on the short term and feasible after acute myocardial infarction and may represent a new therapeutic option in future.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): This research is funded by the sponsor RECARDIO, Inc., 1 Market Street San Francisco, CA 94150, USA. RECARDIO Inc. is funding the complete study. The Scientific Board of RECARDIO designed the study. Data Collection is at the participating sites. Interpretation of the data by the Scientific Board and Manuscript written by the authors and approved by the Sponsor

Duty-cycled multi-electrode radiofrequency vs. conventional irrigated point-by-point radiofrequency ablation for recurrent atrial fibrillation: comparative 3-year data

AIMS

Pulmonary vein isolation (PVI) is an accepted treatment to relieve symptoms in patients with atrial fibrillation (AF). We studied 3 year outcome after PVI guided by duty-cycled multi-electrode radiofrequency (RF) ablation (pulmonary vein ablation catheter, PVAC) and provided comparative data to outcome after conventional PVI (CPVI) using mapping with irrigated, point-per-point RF ablation.

METHODS AND RESULTS

One hundred and sixty-one consecutive patients with symptomatic paroxysmal or persistent AF and minimal heart disease underwent PVI (PVAC, n = 79 vs. CPVI, n = 82). Follow-up (with symptom-guided rhythm monitoring) was truncated at 3 years in all patients. Success was defined as freedom of documented arrhythmia after a single procedure and without antiarrhythmic drug treatment (ADT). Baseline characteristics did not differ between both groups. At 3 years follow-up, single-procedure success without ADT was comparable between PVAC and CPVI (65% vs. 55%, P = NS). The majority of recurrences occurred during the first year (PVAC 79% vs. CPVI 70%, P = NS). The annual rate of very late recurrence (i.e. beyond 1 year) was similar in both groups (10.5% vs. 15%, P = NS).

CONCLUSION

At 3 years follow-up, outcome after PVAC-guided PVI is comparable to conventional isolation by irrigated point-by-point RF ablation. In both strategies, the majority of recurrences occurred in the first year of ablation.

Clinical and fundamental aspects of angiogenesis and anti-angiogenesis

Insight into the fundamental physiological mechanisms of blood vessel development and neoformation has led to the discovery of multiple angiogenic growth factors and inhibitors. To date, at least 5 angiogenesis inhibitors are readily available for clinical use, mainly in the treatment of cancers and age-related macular degeneration. More inhibitors are yet to come and the indications for their clinical use are expected to broaden. Conversely, the use of angiogenic stimulators, although initially promising in animal models and in small uncontrolled pilot studies in patients with ischaemic heart disease or peripheral arterial occlusive disease, could thus far not show any convincing therapeutic improvement. Challenges still remain as to which angiogenic factor or combination of factors should be administered and in which form (protein versus gene), and what route and duration of administration should be used. Further clinical perspective might come from the recent identification of vascular endothelial growth factor (VEGF) as a modifier of the neurodegenerative disease amyotrophic lateral sclerosis (ALS), and as a promising therapy in the treatment of ALS in preclinical animal models. This review discusses the different clinical trials of angiogenic inhibitors and stimulators, preceded by some fundamental aspects of angiogenesis, giving the clinician a brief overview of the most relevant angiogenic topics.

Brown tumour: presenting symptom of primary hyperparathyroidism

The skeletal lesions of primary hyperparathyroidism, including brown tumour, are rare nowadays, with the practice of checking serum calcium levels leading to an earlier diagnosis of hyperparathyroidism. Clinical, laboratory, radiographic and histological investigations can lead to a correct diagnosis. Treatment of brown tumour focuses on the hyperparathyroidism, and is usually followed by a regression of the brown tumour. The diagnosis of hyperparathyroidism and brown tumour should be considered in patients with hypercalcaemia and an osteolytic expansive bone lesion. We present a patient where a brown tumour of the mandible was the presenting symptom of primary hyperparathyroidism.