The rate of acute success is defined as the percent of subjects who received HD Grid mapping and RF energy delivery according to label resulting in acute termination of clinical arrhythmia, defined by termination to sinus rhythm (SR) (or AT if being treated for PersAF) or non-inducibility of clinical arrhythmia after ablation (cardioversion allowed prior to inducibility attempt).

PersAF: Subjects indicated for ablation to treat PersAF in which the HD grid catheter was inserted, and RF energy was applied according to label.

VT: Subjects indicated for ablation to treat VT in which the HD grid catheter was inserted, and RF energy was applied according to label.

For PersAF, the rate of long-term success rate is defined as the percent of subjects who receive HD Grid mapping and RF energy delivery according to label and have had freedom from all atrial arrhythmias (AF/AFL/AT) greater than 30 seconds (as documented by 48-hr Holter at 12-month follow-up) and a new or increased dose in class I/III antiarrhythmic drug (AAD). For VT, the percent of subjects who receive HD Grid mapping and RF energy delivery according to label and have had freedom from recurrence of sustained monomorphic VT and a new or increase dose in class I/III AAD at 6-month follow-up. The percent of subjects who are free from the pre-defined endpoints on or off class I/III AADs is also reported.

PersAF: Subjects indicated for ablation to treat PersAF in which the HD grid catheter was inserted, and RF energy was applied according to label who completed their 12-month follow-up visit.

VT: Subjects indicated for ablation to treat VT in which the HD grid catheter was inserted, and RF energy was applied according to label who completed their 6-month follow-up visit.

Overall procedure time is defined as time from initial catheter insertion to final catheter removal.

PersAF: Subjects indicated for ablation to treat PersAF for which overall procedure time data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which overall procedure time data was available, excluding subjects in which a device was used off-label.

AFL: PersAF-indicated subjects also treated for AFL for which overall procedure time data was available, excluding subjects in which a device was used off-label.

Defined as duration of time RF energy is delivered

PersAF: Subjects indicated for ablation to treat PersAF for which RF time data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which RF time data was available, excluding subjects in which a device was used off-label.

AFL: PersAF-indicated subjects also treated for AFL for which RF time data was available, excluding subjects in which a device was used off-label.

AFL:

Defined as total time subject is exposed to fluoroscopy

PersAF: Subjects indicated for ablation to treat PersAF for which fluoroscopy time data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which fluoroscopy time data was available, excluding subjects in which a device was used off-label.

AFL: PersAF-indicated subjects also treated for AFL for which fluoroscopy time data was available, excluding subjects in which a device was used off-label.

Defined as the total mapping time for the creation of each map (including any new or retrospective map created with Manual, AutoMap, and TurboMap mapping)

Maps generated for subjects with procedures and Advisor HD Grid used as mapping catheter excluding subjects in which a device was used off-label.

Defined as total number of mapping points collected for the creation of each map.

Maps generated for subjects with procedures and Advisor HD Grid used as mapping catheter excluding subjects in which a device was used off-label.

Defined as the total number of mapping points used divided by the relative mapping time

Maps generated for subjects with procedures and Advisor HD Grid used as mapping catheter excluding subjects in which a device was used off-label.

For each type of arrhythmogenic substrate this will be defined as the frequency of substrate type identified in cases that attempted to identify the specific substrate.

PersAF: Subjects indicated for ablation to treat PersAF for which substrate characteristic data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which substrate characteristic data was available, excluding subjects in which a device was used off-label.

AFL: PersAF-indicated subjects also treated for AFL for which substrate characteristic data was available, excluding subjects in which a device was used off-label.

Defined by both the type of map used to define ablation strategy and the frequency each ablation strategy/target was used by physicians.

Maps generated for subjects with procedures and Advisor HD Grid used as mapping catheter excluding subjects in which a device was used off-label.

Assessed by physician survey comparing maps generated with HD Wave electrode configuration to along-the-spline (standard) electrode configurations.

Analyzed maps with original electrode configuration as HD Wave Solution and comparable retrospective map generated in standard configuration

Defined as the ability to maneuver the HD Grid to each specified anatomic location if attempted, the ability to contact cardiac tissue, and the incidence of induced ectopic beats during maneuvering.

PersAF: Subjects indicated for ablation to treat PersAF for which HD Grid maneuverability data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which HD Grid maneuverability data was available, excluding subjects in which a device was used off-label..

Defined as the proportion of electrograms collected with HD Grid that have better quality/less noise than electrograms collected with the ablation catheter at the same cardiac location as assessed by physician survey.

PersAF: Subjects indicated for ablation to treat PersAF for which electrogram signal quality data was available, excluding subjects in which a device was used off-label.

VT: Subjects indicated for ablation to treat VT for which electrogram signal quality data was available, excluding subjects in which a device was used off-label.

Defined by the frequency each ablation strategy/target was used by physicians to treat those indicated for PersAF

Pulmonary vein isolation (PVI) Right Superior Pulmonary Vein (RSPV) Right Inferior Pulmonary Vein (RIPV) Left Superior Pulmonary Vein (LSPV) Left Inferior Pulmonary Vein (LIPV)

PersAF subjects who received electroanatomical mapping with Advisor HD Grid for which ablation strategy data was available, excluding subjects in which a device was used off-label.

Defined by the frequency each ablation strategy/target was used by physicians to treat those indicated for VT.

VT subjects who received electroanatomical mapping with Advisor HD Grid for which ablation strategy data was available, excluding subjects in which a device was used off-label.

Number of subjects in whom the HD Grid is inserted and experienced periprocedural and immediate post procedural (48hrs) procedure- or device- related adverse events.

Subjects who underwent ablation procedure and received electroanatomical mapping with Advisor HD Grid.

Number of subjects in whom the HD Grid is inserted and experienced procedure- or device-related adverse events and cardiovascular serious adverse events between 48 hours and 30 days post-procedure.

Subjects who underwent ablation procedure and received electroanatomical mapping with Advisor HD Grid.

Defined as the proportion of subjects free from an additional ablation procedure to treat indicated cardiac arrhythmia (after a blanking period of 90 days) out of the subjects who received HD Grid mapping and RF energy delivery, and either completed 12 months of follow up or did not complete 12 months of follow up but experienced a repeat ablation before withdrawing from the study (PersAF subjects).

Defined as the proportion of subjects free from an additional ablation procedure to treat indicated cardiac arrhythmia (after a blanking period of 14 days) out of the subjects who received HD Grid mapping and RF energy delivery, and either completed 6 months of follow up or did not complete 6 months of follow up but experienced a repeat ablation before withdrawing from the study (VT subjects), excluding subjects in which a device was used off-label.

PersAF: Subjects indicated for ablation to treat PersAF who received RF energy delivery according to label and electroanatomical mapping with Advisor HD Grid for which 12-month follow-up data regarding repeat ablations was available.

VT: Subjects indicated for ablation to treat VT who received RF energy delivery according to label and electroanatomical mapping with Advisor HD Grid for which 6-month follow-up data regarding repeat ablations was available.

Quality of life (QOL) validated by EQ-5D-5L and Atrial Fibrillation Effect on Quality-of-Life (AFEQT) in PersAF subjects at Baseline, 6 and 12 months after receiving HD Grid mapping and RF ablation.

The visual analogue score (VAS) component of the EQ-5D-5L questionnaire indicate how good or bad a subject's health was on the day the questionnaire was administered. 100 means the best health you can imagine and 0 means the worst health you can imagine.

There are 4 subscales that contribute to the Overall AFEQT Score (Symptoms, Daily Activities, Treatment Concern, and Treatment Satisfaction). The overall AFEQT score is calculated using the first 3 domains and ranges from 0 = worst to 100 = best QoL. Patient satisfaction with treatment is not considered to be a part of a patient's health status and is not included in the summary score calculation.

Available QOL data from enrolled subjects who provided written informed consent, confirmed to meet all inclusion criteria and none of the exclusion criteria, indicated for cardiac electroanatomical mapping and RF ablation procedure to treat persistent atrial fibrillation, and in which the HD Grid catheter was inserted and RF ablation procedure performed.

Quality of Life validated by EQ-5D-5L survey in VT subjects at Baseline, 6 and 12 months after receiving HD Grid mapping and RF ablation. Higher scores mean a better outcome.

The visual analogue score (VAS) component of the EQ-5D-5L questionnaire indicate how good or bad a subject's health was on the day the questionnaire was administered. 100 means the best health you can imagine and 0 means the worst health you can imagine.

Available QOL data from enrolled subjects who provided written informed consent, confirmed to meet all inclusion criteria and none of the exclusion criteria, indicated for cardiac electroanatomical mapping and RF ablation procedure to treat sustained monomorphic ventricular tachycardia, and in which the HD Grid catheter was inserted and RF ablation procedure performed, excluding subjects in which a device was used off-label.

Quality of Life validated by Hospitalization Anxiety and Depression Scale (HADS) survey in VT subjects at Baseline, 6 and 12 months after receiving HD Grid mapping and RF ablation. Percent of subjects scoring in the Normal, Borderline Abnormal, and Abnormal ranges in Anxiety and Depression categories.

Each question on the HADS questionnaire is on a scale of 0-3. 0 mean no anxiety/depression and 3 means high anxiety and depression. All question scores are totaled for a range of 0-21. 0-7 score indicates normal levels of anxiety/depression, 8-10 indicates borderline abnormal anxiety/depression, and 11-21 indicated and abnormal case of anxiety/depression.

Available QOL data from enrolled subjects who provided written informed consent, confirmed to meet all inclusion criteria and none of the exclusion criteria, indicated for cardiac electroanatomical mapping and RF ablation procedure to treat sustained monomorphic ventricular tachycardia, and in which the HD Grid catheter was inserted and RF ablation procedure performed, excluding subjects in which a device was used off-label.

Long-term success is defined as the percent of VT subjects who receive HD Grid mapping and RF energy delivery and have had freedom from recurrence of sustained monomorphic VT and a new or increase dose in class I/III AAD at 12-month follow-up. The percent of subjects who are free from the pre-defined endpoints on or off class I/III AADs is also reported.

Subjects indicated for ablation to treat VT in which the HD grid catheter was inserted, and RF energy was applied according to label who completed their 12-month follow-up visit.