Accurate detection of lead malfunction from ECG-derived bipolar pacing stimulus amplitude.

BACKGROUND: One common mode of lead failure is insulation breach, which may result in myopotential noise and device malfunction. "Pseudo-unipolarization" of bipolar pacing stimuli, as observed from a routine 12-lead electrocardiogram (ECG) due to stimulus current leak, has been observed with insulation breaches. OBJECTIVE: We sought to characterize this electrocardiographic finding to detect this type of lead malfunction. METHODS: A total of 138 transvenous leads were analyzed, including 88 with known malfunction and 50 normal leads. The amplitude of a bipolar pacing stimulus on the ECG was recorded and compared with a control data set of newly implanted leads with bipolar stimuli normalized for output. RESULTS: The malfunction group consisted of 61% right atrium and 39% right ventricle leads with mean pacing output of 2.74 V at 0.5 ms. There was a significant difference in ECG bipolar stimulus amplitudes at time of identification of failure (7.89 ± 7.56 mm/V; P < .001) compared with those of normal leads (0.86 ± 0.41 mm/V). Receiver operating characteristic curve for the prediction of lead malfunction based on absolute ECG amplitude displayed an area under the curve of 0.93 (95% CI, 0.891-0.969). When normalized for programmed stimulus output, a cutoff of 5 mm/V demonstrated a sensitivity of 91% and a specificity of 92% (area under the curve, 0.967; 95% CI, 0.938-0.996). CONCLUSION: The maximum amplitude of a bipolar pacing stimulus on the ECG is significantly lower in normal functioning leads compared with those with known malfunction. This simply derived variable demonstrated good accuracy at identifying lead failure due to insulation breach.

Left Common Iliac Vein Stenting in a Case of Postural Orthostatic Tachycardia Syndrome/Pelvic Pain Overlap.

Postural orthostatic tachycardia syndrome (POTS) is mainly characterized by orthostatic intolerance and positional tachycardia although it frequently involves a myriad of non-specific symptoms that seem to overlap with existing medical conditions. Recent efforts have been made to further classify subtypes of POTS and associated conditions to better delineate underlying pathophysiology in an effort to guide diagnosis and tailor treatment. Here, we present a 22-year-old female with debilitating symptoms of POTS who reported pelvic pain on review of systems and underwent vascular ultrasound of the inferior vena cava, iliac veins, and bilateral lower extremities which revealed the characteristic left common iliac vein compression of May-Thurner syndrome prompting venous stenting which provided systemic symptomatic relief.

Long-Term Cost Analysis of Third-Line Treatment Options for Overactive Bladder.

INTRODUCTION: We aimed to analyze the long-term cost of overactive bladder third-line treatments. METHODS: This insurance claims review analyzed the 2015 to 2020 MarketScan (MKS) claims data set subjects age ≥ 18, diagnosis of overactive bladder (OAB) using ICD-9/ICD-10 codes and receipt of treatment for percutaneous tibial nerve stimulation, sacral neuromodulation (SNM), or botulinum A. Age, gender, treatment types, and cost were extracted. Treatment costs were aggregated at the level of patient and treatment type for total payment and patient contribution by combining copay, coinsurance, and deductible. We used the Wilcoxon rank-sum test for continuous and chi-square test for categorical variables. SAS v9.4 was used for analyses. Significance was set at P < .05. RESULTS: We identified 17,755 patients from the commercial claims MKS and 10,912 patients from the Medicare supplemental (MDC) database with mean age 50.7±11.1 and 75.5±7.6 years, respectively, who underwent ≥ 1 third-line OAB treatment. Patients receiving third-line treatment were predominantly female (84.9%, MKS, 74.8%, MDC). Long-term costs over a 15-year period were estimated. Percutaneous tibial nerve stimulation is the most expensive in terms of total net payment ($105,337.50 MKS, $94,102.50 MDC) and patient contribution ($9177.60 MKS, $3921.00 MDC). Total net payment for botulinum A was $67,968 (MSK), $54,261 (MDC), and patient contribution cost was $2850 (MSK), $1110 (MDC). The most cost-effective option was SNM in terms of both total net payment ($5179.10 MKS, $6099.00 MDC) and patient contribution ($59.10 MKS, $60.00 MDC). CONCLUSIONS: SNM was the most cost-effective third-line treatment for OAB looking over a 15-year period in terms of both total net payment and patient contribution.

Severe Vitamin B12 Deficiency Presenting as Pancytopenia, Hemolytic Anemia, and Paresthesia: Could Your B12 Be Any Lower?

Although severe vitamin B12 deficiency is rare in the United States, recent increases in the adoption of vegan lifestyles have led to a significant rise in the rates of B12 deficiency, along with its hematologic and neurologic sequelae, the latter of which is often irreversible. We describe a case of a 39-year-old male who presented with a several-month history of progressively worsening word-finding difficulties, shortness of breath, and a four-day history of bilateral hand numbness and tingling. Laboratory data revealed pancytopenia with profound anemia. Markers of hemolysis were positive, including elevated indirect bilirubin, disproportionately elevated lactate dehydrogenase (LDH), low haptoglobin, negative direct anticoagulant test, and hypoproliferative reticulocyte index. Blood smear revealed hypersegmented neutrophils and macrocytosis. Vitamin B12 levels were undetectable, and anti-intrinsic factor and parietal cell antibodies were negative. A thorough history revealed a 20-year history of strict veganism without B12 supplementation. He was transfused with packed red blood cells and started on subcutaneous B12 injections with rapid improvement of his symptoms. Early recognition of B12 deficiency causing the constellation of pancytopenia, hemolytic anemia, and neurologic symptoms is vital in preventing irreversible neurologic sequelae. This case also highlights the importance of accurate history taking to aid in early diagnosis of B12 deficiency, especially in the context of rising rates of veganism in the United States.

Same-Day Versus Next-Day Discharge Strategies for Left Atrial Ablation Procedures: A Parallel, Intra-Institutional Comparison of Safety and Feasibility.

BACKGROUND: Head-to-head comparative data for the postoperative care of patients undergoing left atrial ablation procedures are lacking. OBJECTIVE: We sought to investigate complication and readmission rates between patients undergoing same-day (SD) or next-day (ND) discharges for ablative procedures in the left atrium, primarily atrial fibrillation (AF). METHODS: Two electrophysiology centers simultaneously perform left atrial ablations with differing discharge strategies. We identified all patients who underwent left atrial ablation from August 2017 to August 2019 (n = 409) undergoing either SD (n = 210) or ND (n = 199) discharge protocols. We analyzed any clinical events that resulted in procedural abortion, extended hospitalization, or readmission within 72 hours. RESULTS: The primary endpoint of complication and readmission rate was similar between SD and ND discharge (14.3% vs 12.6%, p = 0.665). Rates of complications categorized as major (2.4% vs 3.0%, p = 0. 776) and minor (11.9% vs 9.5%, p = 0.524) were also similar.Multivariable regression modeling revealed no significant correlation between discharge strategy and complication/readmission occurrence (OR 1.565 [0.754 - 3.248], p = 0.23), but a positive association of hypertension and procedure duration (OR 3.428 [1.436 - 8.184], p = 0.006) and (OR 1.01 [1 - 1.019], p = 0.046) respectively. CONCLUSIONS: Left atrial ablation complication and readmission rates were similar between SD and ND discharge practices. Hypertension and procedural duration were associated with increased complication rates irrespective of discharge strategy. These data, which represent the first side-by-side comparison of discharge strategy, suggests same-day discharge is safe and feasible for left atrial ablation procedures.