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To study the long-term visual- and device retention-related outcomes and complications of the Boston Type I Keratoprosthesis (KPro).

Glaucoma is the leading cause of vision loss in eyes with Boston Keratoprosthesis (KPro). Glaucoma drainage devices (GDDs) have been shown to be effective in controlling glaucoma with KPro. Cicatricial conjunctival disease with forniceal shortening is a major challenge and limitation to the use of GDD. In our series, we report the success of fornix reconstruction in cicatricial ocular surface disease as a staged procedure prior to a combined KPro/GDD surgery.

Combination of pars plana vitrectomy with posterior glaucoma drainage implant and Boston keratoprosthesis results in lower rates of de novo glaucoma without increased risks of complications as compared to Boston keratoprosthesis implantation alone.

Background:Catheter ablation is effective in the treatment of arrhythmias. The effect of ablation on Cardiovascular Implantable Electronic Devices (CIED) in long-term follow-up is unknown.Objectives:To study the impact of radiofrequency catheter ablation on various arrhythmias in patients with pacemakers and implantable cardiac defibrillators.Methods:We studied 119 consecutive patients with pacemakers and defibrillators who underwent various catheter-based procedures from 2011 to 2018. Various generator and lead parameters were compared before and after the procedure using paired sample t-test. Incidence of device-related complications was recorded as a percentage.Results:The mean age was 64.5 years. 88 patients had CHF (73.9 %). 63 Patients had CAD (52.9 %). 8.93 % and 41.3 % of patients had single and dual-chamber ICDs respectively. The rest of the patients had dual-chamber or biventricular pacemakers. 63.2 % of patients had Pulmonary Vein Isolation, Atrial Tachycardia, or Atrial Flutter ablation. 13.5 % of patients had AVNRT ablation and 20.3 % of patients had PVC or VT ablation. The Median follow-up interval was 8 weeks. No changes in before or after the ablation procedure in the atrial sensing ( 3.37± 1.60mV vs 3.40 ± 1.95 mV , P .52) and pacing thresholds ( 0.85mV± 0.46mV vs 0.82± 0.43 mV, P .35) , impedance (471.83± 106 ohm vs 447.57± 88.64 ohm , P .07) was noticed. Similarly, there was no difference in RV lead sensing and pacing threshold, but paradoxically there was a decrease in RV impedance after ablation (549.77± 173ohm vs 507.40 ± 129.0 ohms, p <0.004). There was no difference in the LV lead parameters. There were no complications as lead dislodgement, stroke, hypotension, or death.Conclusion:Any type of catheter-related ablation is safe and efficacious in patients with pacemakers and defibrillators and there was no generator or lead-related complications noticed on interval follow-up.

The control of blood pressure, heart rate, cardiac output and systemic vascular resistance by the carotid sinus baroreceptor reflex was studied in six conscious rabbits during states of acute hypervolaemia and acute hypovolaemia. These states were produced by infusing blood equal to 20% and 40%, and withdrawing blood equal to 20% and 35%, of the initial blood volume. The properties of the reflex were characterized by creating sinusoidal pressure changes across the wall of the carotid sinus at a frequency of 0.01 Hz and amplitudes of 54 and 83 mmHg. From the effects of the lower‐amplitude stimulus the dynamic gain of the reflex was calculated for blood pressure, heart rate, cardiac output and systemic vascular resistance. The higher‐amplitude stimulus was used to determine the near maximal responses of the circulatory variables to changes in carotid sinus transmural pressure. The gain for systemic vascular resistance was reduced by hypervolaemia, and increased by 20% hypovolaemia. The gains for heart rate and blood pressure were not affected by hypervolaemia or by 20% hypovolaemia. 35% hypovolaemia reduced the gain for heart rate, but the resting value was close to the upper limit of the reflex response. It also reduced the gain for cardiac output and blood pressure, and the increase in gain for systemic vascular resistance that had been caused by 20% hypovolaemia was not sustained.

1. A method is described for altering the pressure across the wall of the carotid sinus in conscious rabbits by enclosing the carotid bifurcation in a rigid, fluid‐filled capsule. The extracapsular arterial baroreceptors were denervated. 2. The baroreceptor‐‐heart rate reflex, elicited by injecting vasoactive drugs or inflating aortic and vena caval cuffs, was used to test the new method. The function of the carotid sinus was shown to be unaffected by enclosure in the capsule. Denervation of the extracapsular baroreceptors reduced the gain of the baroreceptor‐‐heart rate reflex two‐ to threefold. 3. The characteristics of the carotid baroreceptor reflex were studied in sixteen animals by the capsule method. Median estimates of maximum gain, and the range over which blood pressure changed, were 1.1 mmHg/mmHg and 57 mmHg respectively. There was good agreement between duplicate estimates made 1‐‐20 days apart. 4. There was only a weak association between the effects on blood pressure and heart rate of altering carotid sinus transmural pressure. Autonomic blockade of the heart, so that its rate was fixed, did not reduce the gain or range of blood pressure change.

Background: The present study was performed to identify the factors associated with amputation in patients with blunt injuries to the lower limb associated with arterial injury. The ability of a scoring system to predict the outcome was tested.

1. Blood pressure, heart rate and cardiac output were measured in six rabbits before, during and immediately after treadmill exercise. During the same periods the dynamic gain of the carotid-sinus baroreceptor reflex was estimated by creating a sinusoidal oscillation of carotid-distending pressure. 2. The average blood pressure did not change significantly during or after exercise, but heart rate and cardiac output rose markedly and there was a concomitant fall in systemic vascular resistance. 3. The reflex gain for blood pressure decreased by one-fifth during exercise, and the gains for heart rate and vascular resistance by two-fifths. Immediately after exercise the gains for all three variables decreased further, to between one-half and one-third of the resting values. 4. Our results indicate that during and after dynamic exercise the correction of a potential disturbance of blood pressure by the carotid-sinus baroreceptor reflex is decreased in magnitude or in speed.

Objective:: To determine the incidence and cause for reoperation following aortofemoral bypass surgery. Design:: This paper describes the results of all aortofemoral grafts performed in the years 1978-1991, 251 of these patients underwent an aortobifemoral graft (ABF) whilst the remaining 50 had an aortounifemoral graft (AUF). Results:: The aortofemoral bypass was the only operation performed in fewer than half of the patients. Sixteen per cent of ABF and 50% of the AUF patients had surgery before the index operation. Subsequently 33% of the ABF patients and 60% of the AUF group had one or more additional vascular procedures. Graft infections and false aneurysms continued to present in about 1% patients per year at least up to 10 years following surgery. The 5 year actuarial survival was 73% in the ABF group and 38% in the AUF patients. The primary patency at 5 years was 85% in the ABF patients and 81% in the AUF group. Amputation was performed in 6% of the ABF patients and in 20% of the AUF patients. Conclusions:: The frequent need for later surgery (1:3 for the ABF patients) should be considered in the decision to undertake the initial aortofemoral operation when the patient presents with intermittent claudication.

1. The change in arterial pressure and heart rate resulting from alteration of carotid sinus transmural pressure by a median -34 mmHg and +33 mmHg by means of a variable-pressure neck chamber was tested in seven male volunteer subjects, at rest and during exertion of 35, 45 and 65% of maximum voluntary handgrip. 2. During 60 s of 35 and 45%, and during 30 s of 65%, of maximal voluntary handgrip there was virtually no alteration of the response of blood pressure to alteration in carotid sinus transmural pressure. 3. The bradycardic response to increase in carotid sinus transmural pressure was reduced at various times after the commencement of handgrip at 45 and 65% of maximum voluntary contraction. 4. It is concluded that a reduction in arterial baroreceptor reflex sensitivity does not play an important role in the initiation of the increase in arterial blood pressure and heart rate caused by isometric exercise. 5. The hypothesis is advanced that some of the cardiovascular changes in exercise may result from elevation of the central ‘set point’ for blood pressure.

The records of 65 patients with closed liver injuries were studied in order to determine which of 19 variables might be important in predicting the outcome. The statistical technique of multiple regression analysis was used. The presence of hypotension and of head injury were the most important prognostic factors; on the other hand, the number of associated injuries was not a significant factor. The major problem was the patient with the isolated severe liver injury.

This paper reports the results of reconstructive renal arterial operations on 23 patients who underwent surgery because it was considered that renal artery disease was contributing to their chronic renal failure. The median pre-operative serum creatinine in this group of patients was 0·77 (range 0·15–1·14 mmol/l) and all patients had severe hypertension. In 10 cases there was evidence of other renal disease (analgesic nephropathy, 8; glomerulonephritis, 2). Operation performed was unilateral aortorenal reconstruction in 21 patients and bilateral reconstruction in 2 patients. There were four in-hospital deaths. In 15 patients operation was judged to have improved their renal function with a fall of median pre-operative creatinine from 0·34 mmol/l (0·15–0·84) to a median creatinine of 0·15 (0·05–0·52). There was one intra-operative death. There were 7 patients in whom operation led to no improvement in renal function. Their median pre-operative creatinine was 0·90 (0·32–1·14 mmol/l), and this pre-operative creatinine differs significantly from the group whose creatinine fell after surgery (P< 0·002). Renal artery reconstruction should be considered in patients with chronic renal failure who have correctable arterial lesions.

SummaryThis paper describes a method, using an interactive computer programme, for fitting a curve to data which is expected to assume a sigmoid form. The programme is specifically designed to generate best estimates of the limits and maximum slope of stimulus-response curves for the carotid sinus baroreceptor reflex, but is applicable to curve-fitting tasks in other fields such as immunology, pharmacology, biochemistry and neurophysiology.Australian Journal of Experimental Biology and Medical Science (1979) 57, 39–41; doi:10.1038/icb.1979.4

1. The effects of acute blood volume change in conscious rabbits on a.c. gain of the carotid baroreceptor reflex with respect to heart rate, blood pressure, cardiac output and systemic vascular resistance were studied. 2. With acute, isohaemic increase in blood volume by 20% and 40% the only consistent trend was a decrease in gain for systemic vascular resistance. 3. With acute reduction in blood volume there was a consistent tendency for gain for heart rate to fall. With 20% reduction in blood volume, gain for cardiac output fell but gain for systemic vascular resistance rose and its phase-lag became shorter, so that gain for blood pressure was unaltered. The enhanced gain for systemic vascular resistance was not sustained with 35% reduction in blood volume, so that gain for blood pressure fell. 4. Thus control of blood pressure by the carotid sinus reflex is remarkably unaffected by acute change in blood volume, and is impaired only when there is depression of gain for cardiac output without a concomitant rise in gain for systemic vascular resistance.

Introduction:Left Atrial Appendage Closure (LAAC) is an increasingly popular treatment modality for Atrial Fibrillation (AF). Different approaches including open heart surgery, minimally invasive surgical LAAC, and percutaneous LAAC have been used. However, limited literature exists comparing these approaches.Methods:We queried the 2016 National inpatient sample to identify patients undergoing LAAC using ICD procedure. The total number of procedures, baseline characteristics, procedural outcomes, thoracoscopic LAAC or percutaneous LAAC were analyzed. Procedure-related complications were identified as defined by the Agency for Healthcare Research and Quality.Results:In 2016, LAAC was most frequently performed along with open heart surgery (20,060), as compared to minimal invasive (1,090) or percutaneous approaches (5,885), which are largely standalone procedures. The top four concomitant open-heart surgery performed with LAAC are coronary bypass surgery (50.74%), aortic valve surgery (25.52%), mitral valve surgery (24.52%) and Cox-MAZE procedures (22.68%). Notably, the extraluminal device (e.g. AtriClip) has replaced traditional suture or staple closure as a major approach of surgical LAAC. Percutaneous LAAC was performed on a largely older and higher risk population (higher Chads-Vasc / ATRIA scores) as compared to Minimal invasive surgery. Despite this difference, percutaneous LAACs were associated with significantly lower noncardiac complications (7.81 vs 25.68%, p<0.001), length of stay (1.83 vs 4.75 days, p<0.001), hospitalization costs and a trend towards lower mortality (0.35% vs 0.45% p=0.277) as compared to minimally invasive surgery. (FIGURE 1)Conclusion:Percutaneous LAAC is associated with lower noncardiac complications and shorter hospitalizations despite being performed in an older and higher risk population. Further prospective study is needed to further establish these findings.

Introduction:Coronary revascularization is an integral part of heart failure with reduced ejection fraction (HFrEF) management. However, the utilization of revascularization among patients admitted with HFrEF from national level is not well described.Hypothesis:The utilization of coronary revascularization in patients with HFrEF has increased over time.Methods:We queried the National Inpatient Sample database for systolic heart failure admissions from 2007- 2016. Subcategorization into patients undergoing percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG) or no intervention was performed. Trends in the total number of admissions for HFrEF, rates of PCI or CABG, mortality and complication rates were analyzed using linear regression or Cochran-Armitage test, as appropriate. Predictors for utilization of coronary revascularization were evaluated by logistic regression using demographic and comorbidities variables.Results:Between 2007 and 2016, a decline in total admissions for HFrEF decreased from 871,179 to 441,434, along with a drop in inpatient mortality from 3.3% to 2.88% (Ptrend<0.001). Rates of PCI have increased (0.86% to 1.37%, Ptrend<0.001), with a steady decline in CABG utilization (0.34% to 0.28%, Ptrend=0.001). There was an uptrend in PCI in-hospital mortality (2.61% to 4.39%, Ptrend=0.027) but not in CABG. The revascularization related cardiac complications remained stable from 2007 to 2016 (figure 1). Factors associated with a higher likelihood of undergoing a revascularization procedure include Caucasian race, private insurance, urban or teaching hospital, smoking, diabetes or coronary artery disease.Conclusions:Utilization of PCI in patient admitted for HFrEF has increased despite a decrease in total HFrEF admissions. This trend was accompanied by the raise of PCI in-hospital mortality.

Introduction:Percutaneous left atrial appendage closure (pLAAC) devices like the WATCHMAN device have become popular alternatives for patients with atrial fibrillation (AF) and contraindications to anticoagulation. However, trends in its utilization in the United States are not well studied.Hypothesis:pLAAC has been embraced as an effective treatment option and its utilization has increased in recent years.Methods:We queried the National Inpatient database from 2007-2016 to identify AF patients who underwent pLAAC. Trends in demographic and clinical features of patients undergoing the procedure, indications as well as procedural details were analyzed. Analysis was performed using linear regression or Cochran-Armitage test, where appropriate. Procedure-related complications were identified as defined by the Agency for Healthcare Research and Quality.Results:A steady increase in pLAAC implantation is noted since its introduction as depicted in FIGURE 1 (305 to 5885, Ptrend<0.001). This is in large part related to the dramatic 9-fold increase in implantation rates in recent years (2014 to 2016). With increasing procedural volumes, a decline in procedural complications, as well as mortality, is noted. Additionally, there is a significant decline in the length of stay by nearly half (3.7 to 1.8 days, Ptrend, P<0.001). Of note, a majority of these procedures were performed on an elective basis. With regards to patient characteristics, a trend towards implantation in more elderly, as well as a higher risk population, is observed. (CHADVASC score [2.4 to 3.9, Ptrend<0.001] and ATRIA bleeding risk score [1.4 to 2.6, Ptrend<0.001])Conclusions:Utilization of pLAAC in patients with AF has witnessed a significant increase in recent years. This has been associated with improved procedural and patient outcomes. Of note, this improvement is seen despite a trend towards implantation in a higher risk elderly population.

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