Long Term Outcomes Following Catheter Ablation of Ventricular Tachycardia in Patients with and without Structural Heart Disease.

BACKGROUND Long-term outcomes following ventricular tachycardia (VT) ablation are sparsely described. OBJECTIVES To describe long term prognosis following VT ablation in patients with no structural heart disease (no SHD), ischemic (ICM) and non-ischemic cardiomyopathy (NICM). METHODS Consecutive patients (n=695; no SHD 98, ICM 358, NICM 239 patients) ablated for sustained VT were followed for a median of 6 years. Acute procedural parameters (complete success [non-inducibility of any VT]) and outcomes after multiple procedures were reported. RESULTS Compared with patients with no SHD or NICM, ICM patients were the oldest, had more males, lowest left ventricular ejection fraction (LVEF), highest drug failures, VT storms and number of inducible VTs. Complete procedure success was highest in no SHD, compared ICM and NICM patients (79%, 56%, 60% respectively, P<0.001). At 6 years, ventricular arrhythmia (VA)-free survival was highest in no SHD (77%) than ICM (54%) and NICM (38%, P<0.001) and overall survival was lowest in ICM (48%), followed by NICM (74%) and no SHD patients (100%, P<0.001). Age, LVEF, presence of SHD, acute procedural success (non-inducibility of any VT), major complications, need for non-radiofrequency ablation modalities, and VA recurrence were independently associated with all cause mortality. CONCLUSIONS Long term follow up following VT ablation shows excellent prognosis in the absence of SHD, highest VA recurrence and transplantation in NICM and highest mortality in patients with ICM. The extremely low mortality for those without SHD suggests that VT in this population is very rarely an initial presentation of a myopathic process.

A numerical model for predicting shoreline changes /

A mathematical model for long-term, three-dimensional shoreline evolution is developed. The combined effects of variations of sea level; wave refraction and diffraction; loss of sand by density currents during storms, by rip currents, and by wind; bluff erosion and berm accretion; effects of manmade structures such as long groin or navigational structures; and beach nourishment are all taken into account. A computer program is developed with various subroutines which permit modification as the state-of-the-art progresses. The program is applied to a test case at Holland Harbor, Michigan. (Author).

Beach changes at Holden Beach, North Carolina, 1970-74 /

Beach profile lines at 21 near-evenly spaced intervals along Holden Beach, North Carolina, between Lockwoods Folly and Shallotte Inlets, were measured from November 1970 to December 1974. These have been analyzed to determine the spatial and temporal variabilities on long-term, seasonal, and short-term scales. Profile lines near the inlets showed the greatest variability in mean sea level (MSL) position, above MSL volume, foreshore slope, and profile envelope. This variability near Lockwoods Folly Inlet was partly enhanced by artificial nourishment at profile line 2. Temporary, low-cost shore protection devices (e.g., sandbag groins) were constructed near that inlet during part of the study. No other modifications or activities that affected beach processes were known to occur during the study period. The central part of Holden Beach was studied separately because of the high variability of the inlet sections at either end of the island. Foreshore slopes along this reach increased from an average of 1:30 at the east end to 1:17 at the west. A seasonal change in above MSL volume indicates loss of sand during autumn and winter, and gain during spring and summer. Changes in MSL shoreline intercept and above MSL volume were highly variable during the study.