The AquaPass System is intended for enhancing fluid transfer through the skin, by increased sweat rate, in fluid overloaded patients.

This study will examine safety, performance and usability of the AquaPass device in two phases:

Phase 1: Hospitalization treatment. Phase 2: Home/outpatient clinic treatment

The AquaPass System is intended for enhancing fluid transfer through the skin, by increased sweat rate, in fluid overloaded patients.

This study will examine safety, performance and usability of the AquaPass device in two phases:

Phase 1: Hospitalization treatment: This phase will begin when the patients are hospitalized with chronic heart failure symptoms and fluid overloaded and undergo sequential treatments. This phase will be conducted using a prospective case-control design, with measuring endpoint during hospitalization and follow-up (after discharge).

Phase 2: Home treatment: Upon investigator decision at discharge, patients will use Aqua-Pass device at home or at outpatient, after discharge, aiming to refine fluid management and prevent re-admission. This phase will require a separate Informed Consent Form (ICF) and will be conducted using a prospective single-group pre-post design.

• A multi-center, prospective, open label, one arm study.
• Chronic heart failure patients will be enrolled into the study when admitted to the hospital with fluid overload.
• During the in-hospitalization treatment phase, patients will undergo up to 5 procedures with the Aqua-Pass device between 3-8 hours.
• Following discharge and upon investigator decision, patients will sign a dedicated ICF and continue the Aqua-Pass treatments at home or in the outpatient clinic for up to 60 days, at a rate of 1-4 treatments per week.
• Follow up assessments, either during visit or over the phone, 7±2 days from the last procedure

Inclusion Criteria:

1. Age ≥ 18

2. Subject was hospitalized for worsening of chronic heart failure with fluid overload.

3. Recruitment with expectation for at least 2 additional days in hospital.

4. Subject has composite congestion score ≥3.

5. Baseline systolic blood pressure ≥100.

6. Subject is capable of meeting the following study requirements:

   • Subject is taking a standing diuretic dose of ≥40 mg/day
   • For patients with BMI <30 kg/m2: baseline N-terminal pro b-type natriuretic peptide (NT-proBNP)>1,600 pg/ml
   • For patients with BMI >30 kg/m2: baseline N-terminal pro b-type natriuretic peptide (NT-proBNP) >800 pg/ml
   • For patients with rate-controlled persistent or permanent Atrial Fibrillation (AF): N-terminal pro b-type natriuretic peptide (NT-proBNP) >2,400 pg/ml.

7. Subject completes 2 hours of run-in acclimatization session as follows:

   • Put on the wearable and see if the patient fits inside it comfortably.
   • Turn on console and see if the patient feels well when the skin temperatures are at least 37°C.
   • Blood Pressure, Heart Rate, Core Temperature and have not changed, relative to baseline, by more than 20%.
   • Systolic BP does not drop below 90 mmHg in 2 consecutive measurements.

Exclusion Criteria:

1. Subject is enrolled to another clinical investigation that might interfere with this study.
2. Baseline systolic blood pressure <100 mm Hg
3. Subject considered to be in the acute worsening of the heart failure: Requiring ventilation, mechanical support or is clinically unstable requiring pressors, deterioration triggered by arrythmia, infection or other medical condition unrelated to fluid overload.
4. Subject has any known lower body skin problems (open wounds, ulcers)
5. Subject with severe peripheral arterial disease
6. Subject is pregnant or planning to become pregnant within the study period, or lactating mothers.
7. End-stage renal disease (eGFR<15 ml/min/1.73 m2) or requiring dialysis.
8. Inability or unwillingness to comply with the study requirements.
9. History of heart transplant or actively listed for heart transplant or Left Ventricular Assist Device (LVAD).
10. Implanted left ventricular assist device or implant anticipated <3 months.
11. Malignancy or other noncardiac condition limiting life expectancy to <12 months.