This is a multi-center, open label, phase IV study conducted to evaluate the efficacy and safety of agalsidase beta (Fabrazyme [recombinant form]) administered by intravenous drip infusion in participants with cardiac Fabry disease.

Participants participated for 4 weeks or less in the baseline period and 156 weeks for the treatment period.

Inclusion Criteria:

• Participants definitively diagnosed with cardiac Fabry disease (who fulfill all of the following criteria)

  • In the case of male participants, documented plasma or leukocyte alpha-galactosidase A (α-GAL) activity was no more than 20 percent (%) of normal value (except for heterozygous female participants)
  • Left ventricular hypertrophy was noted.
  • Accumulation of globotriaosylceramide (GL-3) in the myocardium or a genetic deficiency associated with α-GAL was confirmed
  • Or in the case of heterozygous female participants, when the family (father or son) was diagnosed with Fabry disease. (Father or son was related by birth.)
  • Without symptoms or signs of Fabry, such as acroparesthesia, angiokeratomas, abnormal sweating, pain of distal extremities, chronic abdominal pain/diarrhea and corneal opacities were observed, except for proteinuria sign.

• Participants with interventricular and posterior wall thickness of at least 13 millimeter (mm) on echocardiography within 3 months before signed date to informed consent

• Participants in whom cardiac function was rated as Class I or II according to the New York Heart Association (NYHA) classification when giving informed consent.

• Participants classification: inpatients and outpatients

• Participants who had given written informed consent before the study-related baseline tests.

Exclusion Criteria:

• Participants with severe hypertension (for example, blood pressure more than or equal to 180 millimeter of mercury [mmHg] and/or blood pressure more than or equal to 110 mmHg in spite of adequate medication)
• Participants whose serum creatinine level was higher than the upper normal limit within 3 months (12 weeks) prior to giving informed consent.
• Participants who had undergone kidney transplantation or were currently on dialysis.
• Participants with any serious hepatic disorder. Participants who had abnormal hepatic function test values within 3 months (12 weeks) prior to giving informed consent (when either alanine aminotransferase [ALT] or aspartate aminotransferase [AST] level exceeded the value five times as high as the upper normal limit).
• Permanent pacemaker or defibrillator implanted participants
• Pregnant or lactating women
• Participants who had taken this drug for 6 months (26 weeks) or more before giving informed consent.
• Participants who had participated in a clinical study employing any other investigational product within 3 months prior to giving informed consent.
• Enzyme replacement therapy history, except for agalsidase beta
• Participants who were unwilling to comply with the requirements of the protocol.
• Others judged by the investigator or sub-investigator to be ineligible for the study

Efficacy evaluable population (EEP) included all registered participants except those who had serious deviations from protocol compliance requirements, did not receive study drug, had no data available at baseline or after study drug administration, and who were found to have no condition in cardiac Fabry disease.

All Adverse Events (AE) were collected from signature of the informed consent form up to the final visit (Week 156) regardless of seriousness or relationship to investigational product.

Reported adverse events are treatment-emergent adverse events that is AEs that developed/worsened during the 'on treatment period' (from the first study infusion up to Week 156).